I always looked at turbo'd engines as having the smaller displacement when driven softly and a larger displacement when driven hard. Therefore, you will only get good fuel economy when you drive very easily, but you have the option of way more power when you want it. You just have to sacrifice that fuel economy when you want power. Kind of like cylinder deactivation, only more reliable.
Apart from that smaller displacement being tied to lower compression or retarded ignition. Basically you have no power until it's on boost. It would make more sense to have the larger engine and turbo that to the same power level so it can run higher static compression and less boost.
I had (2) 2.0 Direct injection turbo engines, one in a Forester XT the other in a Sky redline. Both rated at about 250-260 HP. My 13' Accord with a 3.5L V6 (rated at 278 HP) and variable displacement was faster and got better fuel economy. The Accord ran on 3cyl when that is all you needed. Problem with a turbo is you are always into the turbo and asking more air and fuel to get moving and stay at highway speeds. If you paid attention to the whole video they reason for these turbo engines is not really fuel efficiency but to get the EPA numbers higher. That does not translate to real world fuel economy. Ask anyone with an eco boost Ford Pickup. The Accord with cylinder deactivation is 100% reliable. before 13' there were issues, especially on vehicles where people didn't step on it so much. Even in the older ones people easily got 200K if the changed the oil regularly.
@Si Raff small turbo engines start boosting at like 1300/1400 revs... there is no safe "no boost" range cause if you drive it below boost you are going to damage your engine
There's only ONE reason why my turbocharged 4 cylinder gets bad gas mileage.... REASON: It's because my foot's in it so far that the fan is clipping my toenails..
Don't had that problem with v6 or v8..... it is fine if you try to cruise on high way but yet again a Bugatti can cruise on the highway.... less power mean more rev and breaking and more rev.... while I just shipped down a few gear..
Yes you are correct. HOWEVER... let’s look at the 718 Boxster for example. The previous gen was a 6 cylinder and the new one is a turbo 4. They promise the same power from the new one with better economy. Perfect right? The problem is however that power is when the car is on boost however the fuel economy numbers are when the car has not hit boost. So you either have better economy or more power but not both. Therefore a turbo 4 is not a replacement for a na 6
Not everyone drives at sea level. Turbocharging makes a huge difference when driving at higher altitudes. For the vast majority of the time, the engine is operating at only a limited throttle opening. Sure, if you smash down on the gas pedal all the time, your fuel mileage will decrease. The advantage of the turbo is that the extra power is there when you need it; entering onto a freeway or climbing steep grades or over-taking slower vehicles. You must factor in the effect of the intercooler in any discussion on engine efficiency.
@@user-zv8qg1co4z I never had a time where my lancer es n/a 120hp engine had me wishing to have more hp to get on a freeway ramp lmao. And on my 18 wrx if I go above 10% foot pedal then rip fuel economy
not necessarily, compression ratios play a pretty big part. two engines can be using the same air fuel ratio at the same displacement, and provided the fuel can handle it, the engine with higher compression will make more power while using the same amount of fuel.
Its efficiency what we are talking about. If you accelerate little with a smaller turbocharged engine it is going to consume less than a naturally aspirated engine. If you accelerate more, it is going to consume more. Consumption tests are done when accelerating little, while in the real world, you may accelerate more, so consumption is higher than its rating, or higher than the former N/A engine.
Not always, but if the extra power comes from forcing more air at once, then yes... because more air always requires more fuel to keep the same A/F ratio. You can make more power and gain efficiency by adding compression or reducing friction. You can also improve breathing, which while not cramming more air per stroke, does shift the powerband into higher revs... since you have to rev higher to make the power afforded by the airflow, you have more strokes.... so you still use more air (and fuel) overall if you want to take advantage of the power gains.
When my Firefly Turbo kicks in around 3000 rpm, it feels like an extra cylinder just started firing. My 3 cylinder, 1 litre suddenly becomes a fire breathing 1300. Hold onto your hats....!!!
It's too slow and fun to drive it recklessly. No airbags in 1991..... Easy to work on....but a death trap any way you look at it. Just incredibly cheap to drive to work.
i see these engines being used in the new fiestas etc in the UK and really wanting to know are they really as effective and powerful as a 4 cyl engine with near enough same HP or even less, there is a fiesta ST model not sure on exact name of model, but its sports a 140hp 3 cyl turbo engine and im just amazed that old 6's didnt make that much more before.
panther105 i had a non turbo Geo Metro, and every two weeks was a massive $35 fill up lol, i now have a 2005 Chevrolet Colorado and $40 is only half a tank now
I have a small (1.4 liter) turbocharged engine in my car. I have never gotten the mileage that I thought I should be getting, and this video helps a bit to understand why this is. The real blow that I got was when my car was in the body shop for a month (let's just say that it was the busy season, and that's all I have to say about that). I had a rental car that was a larger sedan with a V6, and it got better mileage than my smaller car. I still miss that rental car...
I’m surprised you didn’t mention the option of higher octane fuels to help reduce knock. Typically the factory turbo cars use a specific type of programming or ecu tuning called “adaptive octane logic” so the computer can tell how high of octane the fuel it’s using is. Most of the factory turbo cars tend to “recommend 91/93 octane” for this reason. Basically it allows you to use 87 if you want but once the adaptive octane logic sees the fuel is crap it can set a lower cap on the engine timing. So let’s say you use 87 octane. The adaptive octane logic may set the limit of the timing to 12 degrees(advanced) well once you throw 93 in the tank and the sensors sample that fuel it will increase the limit of the timing from 12 degrees to lets say 20 degrees (advanced) resulting in more power out of the same calibration all while keeping the engine safe.
True and a lot depends on how heavy your foot is applied. With a light foot the tranny can shift before the turbo kicks in. This eleminates knocking and the need for high octane fuel. In this scenario, lower octane fuels can get the same MPG w/o spending that extra 10% per gallon. Regular gas ignites easier and burns quicker than premium which can improve MPG in some scenarios. For the lead foot driver, premium offers more power and better MPG but offset by the fuel's expense.
That's because higher octane gasoline doesn't actually affect fuel economy. That sales point is a scam. If that were true, all car manufacturers would design engines for that type of gas, and all gas stations would serve only that type of high octane gas.
@@thresh-idk if I’d use that as a blanket statement for all cases. Especially since if your engine is knocking and the fuel system has to retard the timing to compensate for it. Then in that situation the higher octane would result in better fuel economy. It’s not as cut and dry as most people think who haven’t studied the modern fuel systems in the past 10-15 years honestly. No disrespect intended. People just assume cause they knew long ago it’s the same as it was. And fuel systems and the methods engineers use to control the fuel systems have drastically changed over the past few years.
@@thresh- for someone like me a master tech of over 15 years to hear someone say higher octane dosnt affect fuel economy it just shows people like me you don’t understand Timing, long and short term fuel trims, what octane actually does and how it affects an engine, or how modern fuel system works. Again no disrespect. But when people say blanket statements like that it really shows the uneducated ignorance unfortunately
@@thresh-Domestic car companies are lobbying for a unified 95 octane fuel. Makes sense since we have so much corn ethanol. Lower octane fuel has a little more enthalpy, but not being able to compress it as much is costly.
Idk about all of that, but in my experience, keeping at a lower speed seems to do pretty well. I have a 2013 Ford escape with the 1.6 EcoBoost engine. Epa estimates it at 33 hwy mpg. I can achieve it if I keep it at 65-70. However in Texas most of our speed limits are 75 or hwy. If I run 75, it gets about 28. Well under the advertised amount.
Keep in mind that the highway fuel efficiency ratings are due to the way cars are tested using a dynamometer and the the Highway schedule which is run at 60 mph, not 75 mph. Higher speeds means more drag (proportional to the square of the speed) resulting in lower mpg.
Hook up an OBD to it (if you don't have a gauge) and monitor. Even in cruise there will be some boost - and that's okay - just means you're getting energy out of the exhaust flow to make the small displacement engine behave bigger. Lighter engine=fuel savings.
@@AlanTheBeast100 Well I know OBD2 stats suck. The O2 sensor just sucks at its job(to freaking slow). Plus on some vehicles they have the o2 sensor behind the cat ALSO. SO WHAT IS THE SECOND CAT TELLING THE FIRST O2 SENSOR TO DO? DON'T SAY IT JUST TELLS THE ECU THAT THE CAT IS WORKING! When Pee my brain tells me that i'm peeing (1st o2 sensor) , If when i'm peeing my pee is black (2nd o2 sensor) brain says WTF!!! WHAT DO I DO! It freaking does something.
@@yourbabyboyfriendonlyme2485 I'm not saying it's a substitute for a proper boost gauge, but it does indicate the MP albeit with a slight lag. (I have Bluedriver with an iPhone and it's quite good in this regard - other readers may be better or worse). The important thing here of course is not the OBD-II - it's that turbo on a small engine means more energy extracted for the fuel burned. That's the main point.
Knock is not the only reason for having to use a rich mixture, exhaust gas temperature is also really important. Water cooled integrated exhaust manifolds really help increasing the lambda = 1 operating range. Current Miller Cycle engines like the EA888 Gen 3b can even run stochiometric in their whole operating range. Also, this video really should have had a bsfc diagram in it to show why smaller engines (higher internal pressure) are more efficient at partial load.
Two things: 1) This is not only linked to "small" displacement engines with turbo. It is the same for any *gas* powered engine using a turbo. 2) This is only relevant for gas powered engine. Diesel-turbos is another discussion.
@@electrictroy2010 More air is more diesel burned, but more work is done so efficiency of the engine is the same or even better. Of course fuel consumption is NOT the same thing as efficiency. Exampe: drive at 70km/h, engine load and efficiency is lower, but the car itself is more efficient since there is less power wasted to overcome air resistance. Double the speed to 140km/h, the power required to overcome wind resistance increases 8 times!! (since air drag power increases with the cube of the speed). Far more energy is needed to travel the same distance so the car is less efficient BUT the engine is more heavily loaded and runs more efficiently. Fuel consumption increases even if the engine is more efficient. IE fuel consumption doubles, but the work done quadruples, so the efficiency increses. Another simple experiment, try pulling up a hill in 5th gear and then try the same hill at same speed, so the power required is the same, but in 3rd gear. In 3rd gear load is lower, there is less boost but it will burn more fuel to do the same work as the efficiency is lower. There is no efficiency penalty for high boost on diesels because diesels don't require full load enrichment. In a gasser full load enrichment helps prevent knock but also causes decreased fuel efficiency, so a gasser might even burn less fuel when you downshift for less boost uphill, which is practically never the case in a diesel
Great video! It'd be interesting also to see how say an LS motor stacks up against a DOHC V8. It's interesting to compare how the E92 M3s compare to the Corvettes of the same era in terms of mileage, for example.
Also keep in mind how people drive turbocharged vehicles. When you're driving a big V8 you have to drive slow to get any decent kind of mileage. Where most people who drive turbo cars always have their foot down... Who remembers the old days when you could literally watch the gas needle move in a V8 truck?
DonnaSean this is exactly the problem. These smaller turbocharged engines are usually dramatically more powerful than the naturally aspirated motors the owner was previously driving. Thus the driver accelerates significantly faster than their old car ( horsepower requires fuel either way) and then complains about the economy.
see the gas needle move? that remember my first car, i kind fixed it... but the ECU was think the engine needed more gas. in fact the poor thing barely moved.
I was very impressed with ford focus and its 1L 3cyl turbo, easily got 45mpg. It has a very low torque range so you could run it below 2k rpm and it still pulled nicely. I didnt get it for performance though, wasnt as peppy as a normal 2L.
For a little while I drove a '13 VW CC with a manual and a stage 1 93 tune to about 250whp. I was getting 28-30mpg combined and I could squeeze 36mpg on the highway. I think the real advantage to these turbo engines is you get all the fun while on boost and then when you're cruising on the highway off boost, it turns into a fuel sipper.
A 2.0L @ 14.7psi boost is now a 4.0L. Its really just displacement on demand, going down the highway its a 2.0L again, but when you pass its back to a 4.0L.
I had (2) 2.0 Direct injection turbo engines, one in a Forester XT the other in a Sky redline. Both rated at about 250-260 HP. My 13' Accord with a 3.5L V6 (rated at 278 HP) and variable displacement was faster and got better fuel economy. The Accord ran on 3cyl when that is all you needed. Problem with a turbo is you are always into the turbo and asking more air and fuel to get moving and stay at highway speeds. If you paid attention to the whole video they reason for these turbo engines is not really fuel efficiency but to get the EPA numbers higher. That does not translate to real world fuel economy. Ask anyone with an eco boost Ford Pickup.
I worked for a Lincoln/Mercury dealer back in the very early 80's. In my three years there, we sold one Mercury Capri with the 2.3L turbo four. It was a nice little car but the owner brought it back to us several times complaining about lousy fuel economy. We checked it out each time and it returned proper gas mileage when we were driving it so there was nothing we could do. We talked to her several times and could never figure out what her problem was when she finally said it. "My salesman said I could have V8 performance AND 4-cylinder gas mileage!" Ok, "now" this makes sense. The service manager resisted the temptation to tell her that her salesman lied through his teeth to her and simply said he was mistaken. She could have V8 performance OR 4-cylinder gas mileage but not both at the same time. She didn't like that answer and we were never able to satisfy her on this issue.
It is more efficient to go with a turbo 4 over a V6 but the problem is the power, especially the very low RPM power of the Ford EcoBoost, is addicting and people have a hard time not putting their foot down from a dead stop. LOL
@@ericverster4069 I miss my 1.6 Fiesta ST. Always had power whenever you needed it, regardless of what gear you were in. Too bad the seats killed my back, otherwise I'd still have it.
I’ve got a 2012 Chevy Cruze with the 1.4L I4 Turbo, and I’m completely turning this thing into a project car. I’ve got a wrecked ‘15 Cruze LTZ with the rear axle disc setup that I’m stealing for my Cruze, and I found a ‘13 eco that caught fire and was totaled out I’m gonna be cannabalizing the frame and splice welding pieces into mine to elongate the engine bay so it can accommodate a 2JZ engine with a twin turbo setup. And it’s thanks to watching your channel, among others, that I’ve been able to realize i can make this happen! Yours just taught me the how it all works at it’s base so that i can understand how my vision can come to life. So thank you man
My 85 Kawi 750 turbo motorcycle can get 45+ mpg steady state cruising at 75+ mph. Around town and under high boost that drops to about 7 mpg! Small price to pay for the fun though.
Just to say, Saabs never suffered from knock. Or at least they prevented Knock. They Developed APC in 1986. (Automatic Performance Control). They used the spark plugs as a sensor and detected the onset of knock from the ionisation within the combustion chamber. If knock was about to occur, then timing would be adjusted. And/Or, boost levels reduced. This meant it effectively detected the Octane of the fuel. Better quality of fuel = more power. A Saab 9000 Aero has standard compression ratio. And yet with 98 Octane RON fuel, it can run 1.4 BAR (24 PSI) boost pressure with no knock. Giving a max of 310bhp from its 2.3L 4cyl. Ford are only just getting to that now with the Focus ST and RS.
Most OBD1 and Every OBD2 car i've ever worked on had a knock sensor which is basically just a microphone on the engine block, you can pop the hood while the engine is running and give the engine a light tap with a wrench and you will hear the idle drop because the ECU will pull timing, All ECU's do is advance timing until it senses knock then retards timing back down until it stops thus getting the best ignition timing possible. Nothing special or new.
Yes @ 310bhp the B234R is at Stage3. My point is, a stock engine will run at 1.4 Bar boost with no Knock when using higher quality fuel. FYI: The above is a just a remap. A B234R can be taken to 500bhp on a completely stock engine. They are fully forged from the factory so dont need to be touched. ALL Stock hardware goes to 310bhp. Then you just change the turbo and injectors and head for 500.
good video. what i like about Toyota hybrid system is that no matter how hard i drive it fuel economy stays good. it's really incredible - the combination of naturally aspirated engine and regenerative braking makes for a system that pretty much doesn't care what your right foot is doing - it always returns the same good fuel economy. of course some people may dislike the feeling and sound of an e-CVT but to have responsiveness of a V6 with over 40 mpg in real world driving - i'll take it.
Wow so basically when you are driving under normal highway conditions turbo 4 cylinders get great fuel milage but when you floor it to make boost/horsepower they make bad fuel mileage.... Surprise!
My 2019 Jetta with a manual seems to do better mileage wise than expected with a 1.4L Turbo. Rated at 40 mpg on the highway, I've done a 45 mpg trip, recorded by the cars computer. Still fast enough to punch it on the highway as well, doing zero to sixty in about 8 seconds.
This comment makes no sense. Same exact problem happens in any turbo fed engine, whether sequential or twin or single turbo v12 or v6. Problem is manufacturers are pushing engines to do more with less volume.
StrangeClouds they're not. My wife has a 1.5L EcoBoost powered Fusion SE Nice car, a little bigger than I prefer but I swear on everything that I hold dear, I have watched the Fuel Economy hit 3.5 MPG when burying the throttle. For being a larger "mid-sized" sedan, the 1.5 does pretty well and perhaps in a small application could be a really fun engine but at times I'm certainly reminded that it's not my older Legacy GT. Though it is leaps and bounds more "Luxurious"
This is a good explanation of why fords eco boost had valve carbonization issues when used under load. The rich air fuel mixture used to cool the combustion space resulted in incomplete combustion allowing soot to build up on the exhaust valve and eventually ruining the valve and it’s seat
If you drive like a street racer and punch the throttle all the time, the boost is always on = bad fuel economy. I manage to get 6.5L/100km average on a 200hp 2.0T engine all the time on a small hatchback, so not impossible.
I don't know a lot about engines, so don't flame me, but would adding an intercooler fix the problem of engine knock in this scenario rather than relying on the rich fuel mixture to cool it down?
AERO BLKHWK32 I think even though ur using an intercooler, the amount of air in the cylinders is much higher and as a result the pressure is much higher. So, as pressure increases, temp increases........even though you are supplying cooler air.......
AERO BLKHWK32 Yes. An intercooler (if there's only one turbo, technically it's called an AFTERcooler) reduces knock. Video explains what happens when boost arrives and the ecu increases richness to protect engine. Premise of video is that we all spend >30% of our driving time with foot on floor. In most countries, this is drivel, as your drivers license will be gone before the contents of your fuel tank. Most driving is done with 0% to 15% throttle. Happy place for turbo economy.
He didn't mention it in this video but there is nearly no point running a turbo or compressor without intercooling the gas before it goes into the engine. Also the rich fuel mixture is there to cool the turbo mmainly at high rpm (we are talking about 800°C instead of 950°C+). We made some tests on the engine-bay and as we excellently forgot to turn on the "rich fuel mixture for cooling" in the software, the Turbo-Temp *quickly* went up to 850°C, 900°C is the absolute maximum that system may reach and that is rather over short times. The knock is a different problem to the overheating turbo that is cooled by rich fuel mixture. Cooling the exhaust gases before the Turbo with a intercooler is not easy and shall not effect the efficeny of the Turbo. VW has a watercooled exhaust connector to the turbo that tries to reduce the need of rich fuel mixture. EE already made a video about that thing.
I baught last year a 1.0 TSI Skoda Octavia 115 hp, 200 Nm. I am verry happy with it, i don''t drive it fast until the engine oil gets to 60/70 degrees Celsius, i got an average of 5.8 L/100 Km till now, and that is excellent. It has 1150 KG without the driver, so the weight ratio is 100 HP/Tone which i think is enough. If people learn how to drive a gasoline turbo engine, everyone will see that is more efficient and fun to drive then natural aspirated gasoline or diesel engine(in my opinion).
They are extremely efficient. My Jetta gets 42-48 mpg on the highway depending on how fast I drive. In the city it is around 30 mpg. The car goes from 0-60 in about 8.5 seconds. I couldn’t be happier with it. The only problem with the TSI engine is that I will have to get a carbon cleaning in about 60k miles to keep it in top shape.
@Engineering Explained, your explanation is partially correct, a modern Tcharged engine is efficient at low and high loads, first way to reduce engine knock in modern forced induction engines is EGR valves, secondly water cooled intercoolers. I've driven 1.2 TSI Vw group car for 60.000 miles(company car), city, highway and mixed cycles, it got way better MPG then a naturally aspirated 1.6 MPI(equivalent power natural induction engine), both having around 100hp,
I used to drive a 2012 Buick Regal GS with a 2.0l Turbo LHU engine (manual). It would regularly get 23 mpg as I drove to work. I bought a 2018 Mazda 6 with the 2.5l turbo a month and a half ago, and now I typically get 35-37mpg on the exact same route. I know the 2.5l is tuned very differently and it's a lighter car, but still even for those numbers.. Mazda's real world tuning is legit for my use-case.
DomitionX it depends a lot on the manufacturers because they all default different heat sources by using extra fuel, some of the newer engines use water injectors for cooler temperatures during combustion which requires less wasted fuel to keep the temps down. Also several newer transmission setups involving many more gears allows for cruising at higher speeds at very low rpms which produces much better fuel economy. 9 gears vs 4-5gears lmao what a big difference it makes
I used to drive the "turboed" vehicles back in the 80's (yes, I'm old), and it was the same deal back then -- you had to stand on the gas to get any power. Seems not much has changed since then.
The technology has changed for the better with more efficient turbo designs along with better cooling. But the main principle is the same. They're still a blast to drive but will drink fuel like an alcoholic when you put your foot down. They are designed to do this not only for the demand for more power but to richen the mixture so you don't lean out and fry pistons. One of my favorite turbocharged vehicles is the older Porsche 944. Primarily gutless but had power when you needed it. Not to mention, one of the easiest and smoothest manual transmissions I've ever driven.
When I was leasing a turbo was fine. Now that I own, can’t go wrong with a nice large displacement natural aspirated engine. Mazda 2.5 L Skyactiv 4 cylinder here.
Direct injection can reduce knock, because it waits to squirt fuel into the cylinder right until the piston is almost at TDC. Modern direct injection also has port injection to clean the intake valves and prevent carbon buildup, but the port injection can be used under light loading conditions where there shouldn't be any knock.
I have a question : Couldn't a solution to this problem not be that the Turbo has to come on later/higher on in the revband ? What I mean by that is that the small engine, by low loads, would run under the point where the turbo is actually active, preventing knock and allowing less fuel to be needed. Typically, with modern gear systems, you could imagine having the car at a constant 1'800-2000 rpm highway, and when you need the boost, simply drop one or two gears and the turbo kicks in and you have the power for those, in general short, load scenarios.
as a "proud" 4b11T owner, can confirm the engine has a compression ratio of just 8:1, is slower than mobility schooter when below boost threshold, and gets 15L/100km or worse fuel economy. all that just for them 22psi factory boost (28psi on evos). glad technology has moved on.
That's why for example older Evos and Subies have ridiculously high fuel consumption. Rather big laggy turbo, high boost figures and low compression ratio. So most of the time you drive it like a N/A car because the turbo hasn't spooled yet in normal driving conditions but you give it more throttle because it doesn't move with it's 8:1 compression ratio and isn't efficient at all...
Discoloured Buttflaps, i was able to get 9.5L/100km out of my 2004 Chevrolet Impala, but on the other hand i was able to watch the needle on the gas gauge go down when the gas pedal and carpet were best friends lol
Only time a small 4banger turbo gets better mpg than a 3-3.5L V6, is when your in bumper to bumper traffic. On open roads, your gotta rev up the 4banger turbo alot more to achieve the same speed. Therefore using more gas, the turbo is dumping more heat in ur cylinders.
My friend and I have the same exact cars the only difference is the engine. He has 2016 Ford Escape with the normal 2.0 4 engine and I have 2016 Ford Escape se with 1.6 4 turbo engine. I not only get better hp and torque especially at lower rpms and better fuel efficiency than his engine with more displacement but no turbo. I have seen it the other way where they still get more hp and torque but worse efficiency a lot worse
TheeJoeyLee yea it is and there a ton of plastic covering the engine like most cars. I don’t know why companies do that. I always like the look of an engine. I never liked all the plastic they put all over. I know it protects from dirt and stuff getting on the engine but more often than not they are a huge pain getting off to do work
How to downsize an ICE: E100 Ethanol, low inertia turbo, variable compression (infinity), direct injection, plasma ignition, colder spark plugs. That is the way. E 100 eliminates knocking, low inertia turbo performs better in small exhaust ports, variable compression extracts the better efficiency for every fuel (TRUE FLEX) and every engine demand, Direct injection for efficiency, plasma ignition for faster burn with less advance and better cold starts, colder spark plugs to drain out combustion chamber heat... Electric cars are not necessary...
It depends on the size of the turbo, both the hot and compressor sides, and you're operating RPM range. Put too big of a turbo on a small engine and it wont spool it up. Put too small of one on and you can over spool it requiring waste gate or blowoff valves, and then you can compound the problem by constricting the overall exhaust flow. Size your turbo for your engine's displacement and operating RPM's.
Knock is not from two flame fronts, multi-plug engines have mult fronts. Knock is from the hotspots you mentioned igniting the fuel charge before the piston reaches top dead center so the explosion force is applied to the piston while it is still travelling up.
I don't know why, but in the game Automation I find it very addicting to make a turbocharged 1.1L i3 engine that revs up to 9100 and has peak power and torque at 7100 rpm. It has approx. 240+ hp.
2017 Chevrolet Malibu. 1.5L , When I set the cruise control at 65 I normally get around 43-47 on the highway. Now go to to 70-72 around 36-39. Having the A/C on “eco- car shuts off at red lights with A/C on.”will bring it down about 6-7MPG less city and highway. So far reliable! 73K.
If I understand well, more fuel is injected for cooling in the same way you spray your face because it's hot outside ? Why not directly spray water inside the cylinder, so it bring down the temperature without wasting precious fuel.
It is rare that I read or watch an automotive pundit that has a complete comprehensive understanding modern 4 cycle combustion theory. Even in the trade magazines. Very good! (ASE Master Tech, 31 years)
Smurfeco 2.3 twice the power?? The 3v 5.4 made 310 hp @ 5,000 RPM / 365 TQ @ 3,500 RPM. The newest 5.0 makes 395 HP @ 5,750 RPM / 400 TQ @ 4,500 RPM. Don’t forget that the Ford GT used this engine (modified of course). The block has been proven to make over 1,000 HP reliability. Look at mustang tuners. The new 5.0 only makes 10% more tq but at 1,000 RPM higher than the 5.4. Also, when using E85 the 5.4 made 395 tq.
Trey K I was just trying to say it has way more power in the mustang and gets better fuel economy I didn’t mention specs how they were cause we all know the 5.0 is a better overall engine than the 5.4
Had VW Golf 1.4 TSI and it was really economic. More than 1.6, 1.8 and 2.0 last naturally aspirated cars I had. And of course, even for 1.4 it was so far more powerful. Didn’t got the point 🤔
I had a 2000 Jetta 1.8T, I took excellent care of it, but my best mileage was 26 mpg, worse than that was that over 80,000 miles, routine maintenance and lots of problems, costed over $6,000. Our new 2017 Camry 2.5L naturally aspirated 4 cyl. is getting 35 mpg.
A turbo with inter cooling can also compensate for low density air at high altitudes. Also Toyota/Lexus has the D4-S which uses both port and direct injection which solves some of the issues.
@E5m What you need to understand is the MPG rating was reformulated in 2008 to reflect cold weather starts and higher speed highway driving, hence, the maximum 55 MPH limit to 65, 70, 80 MPH, on so on. Most vehicles lost a 2 MPG rating from the old MPG figures to the current one. Besides, the city/highway numbers show small numbers ranging from low to high with the large numbers being the average. For example, a 6.2 SS Camaro 6 speed gets 16 city, 24 highway. City MPG might say "13" low, "19" high with the big "16" being the average. Highway MPG might say "21" low, "27" high with the big "24" being the average. Then the 16/24 is calculated with 19 being the average between city and highway MPG. The new MPG formula reflects closer average MPG, the OLD MPG formula reflected an average best, but even that can be exceeded by absolute, 100% perfect conditions. Believe it or not, traveling 3 car lengths behind a car in front of you can artificially raise fuel economy due to less wind resistance. Behind a large SUV, MPG goes even higher. Behind a large semi truck, MPG goes even higher.
In diesel engines, fuel auto-ignition is the goal (diesel engines don't have sparkplugs). It's not a problem, it's normal. For petrol it's a problem because the fuel is supposed to be ignited only by a sparkplug and nothing else.
VW has a compact car for the Brazilian market, called UP TSI. It produces an amazing 110HP with only 3 cylinders and 1000CC of displacement. The turbo works with some 28PSI and it is considered the most fuel efficient car in production. Hard to determine efficiency when the driver's foot is what makes the difference at the end of the day (or when the light turns green!).
I now live in Costa Rica and I have big ol' American Suburban where most Ticos have small 4 cyl engines. This region has tons of hills and mountains. My big V8 gets about the same MPGs as their cars but I can carry 8 people plus a horse and a dead cat. I rev about 1,500 going up mountains while my in-laws small 4cyl is at about 3-4k with four people.
My Mk 7 GTI once returned an impressive 42 mpg driving from Bend, Oregon to Portland, Oregon. Mostly fast-ish, sweeping roads, a decent amount of climbing, and I was stuck in, "stop/start, slow to a crawl" traffic for a good 10 miles. I didn't think it was real...but it was.
How to save fuel: mid 90s sedan 0 to 60...ok at 10s. 2018 f150 4x4 that can tow 9000lb and weighs 4500lb for your whole family...journalists say it's slow unless it can do 60 in like 7 second. Europe saves gas by downsizing on weight and power. We want cake and ice cream and gummy bears
Exactly. In america our vehicles & us need to loose some weight. Ridiculous how we have to carry 3-5000 pounds of metal plastic glass,& rubber with us every where we go. Perhaps we need more Personal Electric vehicles on a smaller separate road network like a bike trail,(or modified bike trails) to avoid collisions with heavier vehicles.
I have the 1.0L ecoboost in my Fiesta and I have a lead foot. The turbo kicks in at around 1500 RPM because the turbo is so small, meaning I am on boost almost all the time when I am not cruising. Even so, I am still getting over 40 MPGs. My milage is almost exclusively highway, so even though I am flooring it all the time when I can, my lead foot makes little difference because of the time I spend cruising. I also drive 5-speed manual if that helps. So for me, it is kind of hard to tell what my milage would be if I did exclusively city driving with constant starts and stops.
Thanks for explaining what I have noticed with cars I have owned/own. My current vehicle (small turbo) gets poorer mileage than my previous model of the same car (larger non-turbo).
2022 Tiguan here. I always beat the EPA numbers handedly. I get about 28 around town and 34 on the highway eve at 80mph. The small turbo by them is great, but I'm not willing to bet on other brands.
If I want econ I'm getting a I4 diesel or a hybrid. The other thing people forget if they are trying to save money specifically at the pump is that a turbo charged engine needs premium fuel, not regular. So anything you might have saved by running a small turbo I4 like a granny is lost by the cost of the better fuel.
I have a 1.0l TSI 3-cylinder engine in Škoda Fabia, my long-term consumption is around 5l/100km (47 MPG) - I consider this to be acceptable consumption for a small engine. When driving on the highway at speed 150km/h (93 miles/h), the current consumption is 7l (33.6 MPG).
My Honda Civic 1.5t is insanely efficient. Runs lean with no boost and gets 50mpg with a light foot. But yes, if you use all 170HP, you get that relative economy. Honda figured it out. I suspect the turbo location (integrated with the exhaust header) and some enhancements in head and piston shape make it work.
I went from a 1.5L Yaris (solid 5.9LPH) to a 1.2L-T Fabia. The Fabia can occasionally get down to 5.0LPH but any sign of traffic or high load and the economy dies. Also bear in mind it is infinitely more complex than the Yaris ie: turbo, liquid intercooler, regen alternator, idle stop, higher octane. I'm not convinced a small turbo was the way to go it is a bit more torquey but that's it. Great vid.
Two Spiralmaxes in the exhaust and two in the intake. With A drop-in K&N air filter. I get better MPGs than the NA version of my car that has the same displacement. I also have AWD...
Moral of the story: for the common person, who bought a car with a tiny turbo'd engine looking for fuel economy, limit throttle to 50% and never go higher. Or you could use e85 and eliminate knock throughout the entire powerband and rev range.
My Lexus RC 200T does great. 25mpg around town, 31 mpg highway with cruise. Unless I keep putting my foot in it. You are correct, good information. Thanks
We had a 2016 equinox with a 2.5 four cylinder that I could get 36 mile per gallon on the interstate and turnpike and around 22 around or home. Our new 2019 equinox has a much smaller 1.5 turbo charged engine. It does get a little better around our house, about 29 mpg, but worse in interstate turnpike driving about 34 mpg.
Perhaps you could investigate power point for better presentation results. I always thought that they could combine gas and diesel with a spark plug to ignite a tiny bit of gasoline injected on top of the diesel fuel, as I thought the gasoline would ignite better. Apparently you seem to indicate that the science works differently than my intuitive reasoning. So very interesting indeed.
My 1.8T Golf has just over 100,000km on it. I live in Calgary, Canada, so we’re at a pretty high altitude. My car has gotten 7.8L/100km combined since I bought it. On long highway cruises, it gets between 5-6L/100km, and in rare occasions can touch 4.9. Is it efficient during city driving? Not really. But there isn’t a non-hybrid vehicle available that is. Turbos are awesome.
@@wiredforstereo That certainly depends on how I drive it, what mode the car is placed in, such as dynamic, comfort, etc.., It really depends on mood I am in. What numbers are you specifically interested in, without having to pay for dyno..? Off the top of my driving very conservatively prior to APR II I avg 23-24mpg after I easily get 27-28mpg city. Driving moderately aggressive prior to stage II would be 18mpg avg.. after stg II its been 22-24mpg. Driving very aggressive I have seen it between 16-18mpg depending on traffic. So to me with this sports Sedan with Quattro (AWD), Yes it is "great".
@@cyb3rcub My naturally aspirated Asian sedan gets 35 mpg and has 300,000 miles. The only way I get mileage like yours is when I'm towing a camper. Different goals I guess, but 24 is certainly not "great MPG" in my book.
@@wiredforstereo 300k Very nice! What car is it as I can't imagine 35mpg in city driving conditions at all?? If I did not have stop and go traffic this bad here I know it would be higher. Not 35mpg but more around 28mpg. Now highway mpg is another story then yes 32-35mpg.
@@cyb3rcub 05 Corolla, 1zz-fe engine. If I drive slower on the highway, I can get 42+. Have clocked 52 with a strong tail wind. As low as 15 pulling a heavy trailer.
The video is correct, in short OEM's are computing fuel economy based on "real world" driving tests that rely on the drivers "not" engaging the turbo. It's actually been proven that larger V8's can get better economy because you do not have to constantly rev the engine to get the needed power.
How are pumping losses lower? Pumping for more power is harder in a smaller engine with smaller/less ports. Most of the benefit in a turbo is that the air can be cooled after compression. Compression makes engines more efficient, lower piston compression means more turbo compression. Power is limited by charge temperature compressed at TDC. So Turbo compression is less limited, and bigger intercoolers can mean more power/less knock is possible. The idea is that fuel economy comes from partial throttle, and overfueling is applied at full throttle only. Nothing wrong with that being under control by the driver. You can also use water injection instead of fuel, or to make your intercooler more effective, but everyone likes the popping and banging of overfuelling.
When I had a fiesta st, it would do fine cruising on the highway and around town as long as it was flat. If I hit even a moderate hill, the engine would dump fuel because the turbo was in its power band.
I’ve got a 1.4 liter turbo Jetta (2017) - It gets 40mpg on the highway, 0-60 in under 8 secs, and usually 36mpg around town. I’ve yet to have any problems with the car. It has the room of a midsize, the acceleration of a v-6, the economy of a subcompact. I’m not sure how you can ask for much more from a cheep compact car than that ($16k new in 2017).
Today I drove 500km with Opel Crossland X with 1.2 turbo threecylinder. It was mix of 40/40/20 highway/ countryroads/city . My fuel economy was 6.4 l/100km that is around 37mpg which is very good. Engine has 81kw and feels faster then my 318i 105kw bmw.
People forget - your right foot is connected to a valve. That valve drains your wallet ;)
You mean that valve is then connected to your wallet!
@@MFizzle777 Oh shut up.
i smell the foot where it is burning the notes TT
This aged like fine wine. 😭
Agree, i can go through liters in ten minutes or 1 hour depending on how heavy it is lol
I always looked at turbo'd engines as having the smaller displacement when driven softly and a larger displacement when driven hard. Therefore, you will only get good fuel economy when you drive very easily, but you have the option of way more power when you want it. You just have to sacrifice that fuel economy when you want power. Kind of like cylinder deactivation, only more reliable.
Apart from that smaller displacement being tied to lower compression or retarded ignition.
Basically you have no power until it's on boost. It would make more sense to have the larger engine and turbo that to the same power level so it can run higher static compression and less boost.
I had (2) 2.0 Direct injection turbo engines, one in a Forester XT the other in a Sky redline. Both rated at about 250-260 HP. My 13' Accord with a 3.5L V6 (rated at 278 HP) and variable displacement was faster and got better fuel economy. The Accord ran on 3cyl when that is all you needed. Problem with a turbo is you are always into the turbo and asking more air and fuel to get moving and stay at highway speeds. If you paid attention to the whole video they reason for these turbo engines is not really fuel efficiency but to get the EPA numbers higher. That does not translate to real world fuel economy. Ask anyone with an eco boost Ford Pickup.
The Accord with cylinder deactivation is 100% reliable. before 13' there were issues, especially on vehicles where people didn't step on it so much. Even in the older ones people easily got 200K if the changed the oil regularly.
@Si Raff small turbo engines start boosting at like 1300/1400 revs... there is no safe "no boost" range cause if you drive it below boost you are going to damage your engine
unheardNerd Go on then - what damage will it do if you drive off boost? This should be good.
he did a very long video about this. driving in low revs. i dont remeber the name
A turbo engine is great power when you kick it and eco when you don´t. Its that simple
Which mean if I dont push the gas too much I can save more fuel?
@@MMizie if you dont push the gas at all you save all the fuel, amazin right?
You have eco or boost. You cant have both.
Carlos Soriano Q
Some say the flat torque curve means a turbo is less exhilarating to floor it. And a little boring to drive.
There's only ONE reason why my turbocharged 4 cylinder gets bad gas mileage....
REASON: It's because my foot's in it so far that the fan is clipping my toenails..
An that's because its gutless ;)
You might want to trim your toenails.
You're so cool Space cadet
Don't had that problem with v6 or v8..... it is fine if you try to cruise on high way but yet again a Bugatti can cruise on the highway.... less power mean more rev and breaking and more rev.... while I just shipped down a few gear..
Yes you are correct. HOWEVER... let’s look at the 718 Boxster for example. The previous gen was a 6 cylinder and the new one is a turbo 4. They promise the same power from the new one with better economy. Perfect right? The problem is however that power is when the car is on boost however the fuel economy numbers are when the car has not hit boost. So you either have better economy or more power but not both. Therefore a turbo 4 is not a replacement for a na 6
in short : you're Jeremy Clarkson , or James May
seems legit.
Hammond doesnt count because hes crashed the car?
hybrid of those two
@@christianbro2 he's very good at coming to a quick and sudden stop
@@GrockleTD Which is not very economical if you think about it
Not everyone drives at sea level. Turbocharging makes a huge difference when driving at higher altitudes.
For the vast majority of the time, the engine is operating at only a limited throttle opening. Sure, if you smash down on the gas pedal all the time, your fuel mileage will decrease. The advantage of the turbo is that the extra power is there when you need it; entering onto a freeway or climbing steep grades or over-taking slower vehicles.
You must factor in the effect of the intercooler in any discussion on engine efficiency.
The air forces realized in WW II that superchargers ( turbos cousin) increased high altitude hp.
@@user-zv8qg1co4z I never had a time where my lancer es n/a 120hp engine had me wishing to have more hp to get on a freeway ramp lmao. And on my 18 wrx if I go above 10% foot pedal then rip fuel economy
All the Coloradans raise their hands 😝
@@LunarStrike mine could do burnouts in 2nd-3rd. Beast of a car for what it was
All I heard was V8s are more efficient and I should drive my turbo car fast for better mileage. Don't correct me, this is the world I want to live in.
Danny Daskalakis That’s my world as well
I like your world, which is why I have the best of both ends described by you: turbo-six :D
Larger engines just make the power easier. Don't need all the turbos, cooling lines etc just to make 400 horse with a v8
Is your world Venezuela ?
Playboysmurf in Venezuela there are no cars to start with
You mean to say that when my engine is making more power, it's also using more fuel? Say it ain't so!
It's not so
not necessarily, compression ratios play a pretty big part. two engines can be using the same air fuel ratio at the same displacement, and provided the fuel can handle it, the engine with higher compression will make more power while using the same amount of fuel.
Its efficiency what we are talking about. If you accelerate little with a smaller turbocharged engine it is going to consume less than a naturally aspirated engine. If you accelerate more, it is going to consume more. Consumption tests are done when accelerating little, while in the real world, you may accelerate more, so consumption is higher than its rating, or higher than the former N/A engine.
Not always, but if the extra power comes from forcing more air at once, then yes... because more air always requires more fuel to keep the same A/F ratio. You can make more power and gain efficiency by adding compression or reducing friction. You can also improve breathing, which while not cramming more air per stroke, does shift the powerband into higher revs... since you have to rev higher to make the power afforded by the airflow, you have more strokes.... so you still use more air (and fuel) overall if you want to take advantage of the power gains.
The answer is more stickers
lmfao.....
Evan Moon And the flame paint job
"This sticker added 5hp"
I started putting racing stickers on my computer i havent noticed a difference at all.
The answer is water ethanol injection. Just look up the german BF109 late variants.
When my Firefly Turbo kicks in around 3000 rpm, it feels like an extra cylinder just started firing. My 3 cylinder, 1 litre suddenly becomes a fire breathing 1300. Hold onto your hats....!!!
Stay safe out there!
It's too slow and fun to drive it recklessly. No airbags in 1991..... Easy to work on....but a death trap any way you look at it. Just incredibly cheap to drive to work.
i see these engines being used in the new fiestas etc in the UK and really wanting to know are they really as effective and powerful as a 4 cyl engine with near enough same HP or even less, there is a fiesta ST model not sure on exact name of model, but its sports a 140hp 3 cyl turbo engine and im just amazed that old 6's didnt make that much more before.
panther105
i had a non turbo Geo Metro, and every two weeks was a massive $35 fill up lol, i now have a 2005 Chevrolet Colorado and $40 is only half a tank now
pescod96 look at Carwow's comparison between the 3 cylinder and 4 cylinder Fiesta ST
I have a small (1.4 liter) turbocharged engine in my car. I have never gotten the mileage that I thought I should be getting, and this video helps a bit to understand why this is. The real blow that I got was when my car was in the body shop for a month (let's just say that it was the busy season, and that's all I have to say about that). I had a rental car that was a larger sedan with a V6, and it got better mileage than my smaller car. I still miss that rental car...
yeah, you have to drive like "that annoying slow person" to get those rates.
I usually prefer Naturally aspirated engines but, twin turbo 3.0 V6s are quite nice.
Turbo lag is a killer though
I’m surprised you didn’t mention the option of higher octane fuels to help reduce knock. Typically the factory turbo cars use a specific type of programming or ecu tuning called “adaptive octane logic” so the computer can tell how high of octane the fuel it’s using is. Most of the factory turbo cars tend to “recommend 91/93 octane” for this reason. Basically it allows you to use 87 if you want but once the adaptive octane logic sees the fuel is crap it can set a lower cap on the engine timing. So let’s say you use 87 octane. The adaptive octane logic may set the limit of the timing to 12 degrees(advanced) well once you throw 93 in the tank and the sensors sample that fuel it will increase the limit of the timing from 12 degrees to lets say 20 degrees (advanced) resulting in more power out of the same calibration all while keeping the engine safe.
True and a lot depends on how heavy your foot is applied. With a light foot the tranny can shift before the turbo kicks in. This eleminates knocking and the need for high octane fuel. In this scenario, lower octane fuels can get the same MPG w/o spending that extra 10% per gallon. Regular gas ignites easier and burns quicker than premium which can improve MPG in some scenarios. For the lead foot driver, premium offers more power and better MPG but offset by the fuel's expense.
That's because higher octane gasoline doesn't actually affect fuel economy. That sales point is a scam. If that were true, all car manufacturers would design engines for that type of gas, and all gas stations would serve only that type of high octane gas.
@@thresh-idk if I’d use that as a blanket statement for all cases. Especially since if your engine is knocking and the fuel system has to retard the timing to compensate for it. Then in that situation the higher octane would result in better fuel economy.
It’s not as cut and dry as most people think who haven’t studied the modern fuel systems in the past 10-15 years honestly.
No disrespect intended. People just assume cause they knew long ago it’s the same as it was. And fuel systems and the methods engineers use to control the fuel systems have drastically changed over the past few years.
@@thresh- for someone like me a master tech of over 15 years to hear someone say higher octane dosnt affect fuel economy it just shows people like me you don’t understand Timing, long and short term fuel trims, what octane actually does and how it affects an engine, or how modern fuel system works.
Again no disrespect. But when people say blanket statements like that it really shows the uneducated ignorance unfortunately
@@thresh-Domestic car companies are lobbying for a unified 95 octane fuel. Makes sense since we have so much corn ethanol. Lower octane fuel has a little more enthalpy, but not being able to compress it as much is costly.
Idk about all of that, but in my experience, keeping at a lower speed seems to do pretty well. I have a 2013 Ford escape with the 1.6 EcoBoost engine. Epa estimates it at 33 hwy mpg. I can achieve it if I keep it at 65-70. However in Texas most of our speed limits are 75 or hwy. If I run 75, it gets about 28. Well under the advertised amount.
This has to do with gear ratios, mostly. The beginning of your last gear is around 60mph, so under 70 you're still in the low revs
@@kingsford6540 air resistance is also considerably higher
Keep in mind that the highway fuel efficiency ratings are due to the way cars are tested using a dynamometer and the the Highway schedule which is run at 60 mph, not 75 mph. Higher speeds means more drag (proportional to the square of the speed) resulting in lower mpg.
Stay out of boost and your gas mileage will be good 🤷🏻♂️ (really hard to do sometimes)
hard to do when it makes 9ft.lbs of torque without boost.
Hook up an OBD to it (if you don't have a gauge) and monitor. Even in cruise there will be some boost - and that's okay - just means you're getting energy out of the exhaust flow to make the small displacement engine behave bigger. Lighter engine=fuel savings.
Kris91790 Very true. Really difficult when the turbos start spoiling at 1,700 rpm though, but it saves gas.
@@AlanTheBeast100 Well I know OBD2 stats suck.
The O2 sensor just sucks at its job(to freaking slow).
Plus on some vehicles they have the o2 sensor behind the cat ALSO.
SO WHAT IS THE SECOND CAT TELLING THE FIRST O2 SENSOR TO DO?
DON'T SAY IT JUST TELLS THE ECU THAT THE CAT IS WORKING!
When Pee my brain tells me that i'm peeing (1st o2 sensor) , If when i'm peeing my pee is black (2nd o2 sensor) brain says WTF!!! WHAT DO I DO!
It freaking does something.
@@yourbabyboyfriendonlyme2485
I'm not saying it's a substitute for a proper boost gauge, but it does indicate the MP albeit with a slight lag. (I have Bluedriver with an iPhone and it's quite good in this regard - other readers may be better or worse).
The important thing here of course is not the OBD-II - it's that turbo on a small engine means more energy extracted for the fuel burned. That's the main point.
Knock is not the only reason for having to use a rich mixture, exhaust gas temperature is also really important. Water cooled integrated exhaust manifolds really help increasing the lambda = 1 operating range. Current Miller Cycle engines like the EA888 Gen 3b can even run stochiometric in their whole operating range.
Also, this video really should have had a bsfc diagram in it to show why smaller engines (higher internal pressure) are more efficient at partial load.
Two things:
1) This is not only linked to "small" displacement engines with turbo. It is the same for any *gas* powered engine using a turbo.
2) This is only relevant for gas powered engine. Diesel-turbos is another discussion.
It applies to turbo diesel too. More air is more diesel burned (and my 51 mpg Jetta TDI drops into the 30s)
.
@@electrictroy2010 More air is more diesel burned, but more work is done so efficiency of the engine is the same or even better. Of course fuel consumption is NOT the same thing as efficiency. Exampe: drive at 70km/h, engine load and efficiency is lower, but the car itself is more efficient since there is less power wasted to overcome air resistance. Double the speed to 140km/h, the power required to overcome wind resistance increases 8 times!! (since air drag power increases with the cube of the speed). Far more energy is needed to travel the same distance so the car is less efficient BUT the engine is more heavily loaded and runs more efficiently. Fuel consumption increases even if the engine is more efficient. IE fuel consumption doubles, but the work done quadruples, so the efficiency increses.
Another simple experiment, try pulling up a hill in 5th gear and then try the same hill at same speed, so the power required is the same, but in 3rd gear. In 3rd gear load is lower, there is less boost but it will burn more fuel to do the same work as the efficiency is lower. There is no efficiency penalty for high boost on diesels because diesels don't require full load enrichment. In a gasser full load enrichment helps prevent knock but also causes decreased fuel efficiency, so a gasser might even burn less fuel when you downshift for less boost uphill, which is practically never the case in a diesel
Then explain how semi trucks can still average 6-8 mpg towing dry vans when 10 is the most they ever will do?
@Chris Russell Shhhh elect........ might learn something.
Granted it is 4 grade stuff.
I just wish they had . well telling would be telling. sorry
@@kennedy796 these engine are like huge 14L V8 engines. How do you expect a good milage from such a huge engine?
Great video! It'd be interesting also to see how say an LS motor stacks up against a DOHC V8. It's interesting to compare how the E92 M3s compare to the Corvettes of the same era in terms of mileage, for example.
Also keep in mind how people drive turbocharged vehicles. When you're driving a big V8 you have to drive slow to get any decent kind of mileage. Where most people who drive turbo cars always have their foot down... Who remembers the old days when you could literally watch the gas needle move in a V8 truck?
DonnaSean this is exactly the problem. These smaller turbocharged engines are usually dramatically more powerful than the naturally aspirated motors the owner was previously driving.
Thus the driver accelerates significantly faster than their old car ( horsepower requires fuel either way) and then complains about the economy.
‘71 Olds Toronado ... 455cid, kick in the 4 barrel over 70mph and just watch the gauge drop 1/10 every few seconds
I just rented a Kia Soul that did that from full tank to a half a tank Driving 80 on a short 80 mile trip. Watched the needle move.
70 Chevelle 396 ss w/cowl, yup it def was a race, those were the days
see the gas needle move? that remember my first car, i kind fixed it... but the ECU was think the engine needed more gas.
in fact the poor thing barely moved.
I was very impressed with ford focus and its 1L 3cyl turbo, easily got 45mpg. It has a very low torque range so you could run it below 2k rpm and it still pulled nicely. I didnt get it for performance though, wasnt as peppy as a normal 2L.
For a little while I drove a '13 VW CC with a manual and a stage 1 93 tune to about 250whp. I was getting 28-30mpg combined and I could squeeze 36mpg on the highway. I think the real advantage to these turbo engines is you get all the fun while on boost and then when you're cruising on the highway off boost, it turns into a fuel sipper.
A 2.0L @ 14.7psi boost is now a 4.0L. Its really just displacement on demand, going down the highway its a 2.0L again, but when you pass its back to a 4.0L.
SP392 not exactly but first comment worth giving a thumbs up
close enough ;)
The big difference being flow rates, intake air temps and active vs static compression but you're not all that far off.
There is no replacement for displacement.
I had (2) 2.0 Direct injection turbo engines, one in a Forester XT the other in a Sky redline. Both rated at about 250-260 HP. My 13' Accord with a 3.5L V6 (rated at 278 HP) and variable displacement was faster and got better fuel economy. The Accord ran on 3cyl when that is all you needed. Problem with a turbo is you are always into the turbo and asking more air and fuel to get moving and stay at highway speeds. If you paid attention to the whole video they reason for these turbo engines is not really fuel efficiency but to get the EPA numbers higher. That does not translate to real world fuel economy. Ask anyone with an eco boost Ford Pickup.
I worked for a Lincoln/Mercury dealer back in the very early 80's. In my three years there, we sold one Mercury Capri with the 2.3L turbo four. It was a nice little car but the owner brought it back to us several times complaining about lousy fuel economy. We checked it out each time and it returned proper gas mileage when we were driving it so there was nothing we could do. We talked to her several times and could never figure out what her problem was when she finally said it. "My salesman said I could have V8 performance AND 4-cylinder gas mileage!" Ok, "now" this makes sense. The service manager resisted the temptation to tell her that her salesman lied through his teeth to her and simply said he was mistaken. She could have V8 performance OR 4-cylinder gas mileage but not both at the same time. She didn't like that answer and we were never able to satisfy her on this issue.
It is more efficient to go with a turbo 4 over a V6 but the problem is the power, especially the very low RPM power of the Ford EcoBoost, is addicting and people have a hard time not putting their foot down from a dead stop. LOL
lol the 2.3s are wicked fun. 5.0 not too shabby either.
@@ericverster4069 I miss my 1.6 Fiesta ST. Always had power whenever you needed it, regardless of what gear you were in. Too bad the seats killed my back, otherwise I'd still have it.
lmao my moms Escape with the eco boost is fun as hell to drive. it’s quick at the low end
I'd personally take the duratech family of engines over any of the ecoboosts in terms of reliability.
I would take a good v6 over a turbo 4 any day
Love this video finally answer my question about why i get better gas milage in a 2.5L L6 BMW than a 2.0T in a Tucson
2.0 better gas 2.5 go fast
I’ve got a 2012 Chevy Cruze with the 1.4L I4 Turbo, and I’m completely turning this thing into a project car. I’ve got a wrecked ‘15 Cruze LTZ with the rear axle disc setup that I’m stealing for my Cruze, and I found a ‘13 eco that caught fire and was totaled out I’m gonna be cannabalizing the frame and splice welding pieces into mine to elongate the engine bay so it can accommodate a 2JZ engine with a twin turbo setup. And it’s thanks to watching your channel, among others, that I’ve been able to realize i can make this happen! Yours just taught me the how it all works at it’s base so that i can understand how my vision can come to life. So thank you man
My 85 Kawi 750 turbo motorcycle can get 45+ mpg steady state cruising at 75+ mph. Around town and under high boost that drops to about 7 mpg! Small price to pay for the fun though.
Just to say, Saabs never suffered from knock. Or at least they prevented Knock. They Developed APC in 1986. (Automatic Performance Control). They used the spark plugs as a sensor and detected the onset of knock from the ionisation within the combustion chamber. If knock was about to occur, then timing would be adjusted. And/Or, boost levels reduced.
This meant it effectively detected the Octane of the fuel. Better quality of fuel = more power.
A Saab 9000 Aero has standard compression ratio. And yet with 98 Octane RON fuel, it can run 1.4 BAR (24 PSI) boost pressure with no knock. Giving a max of 310bhp from its 2.3L 4cyl. Ford are only just getting to that now with the Focus ST and RS.
No SAAB 9000was getting 310 hp stock... and modified it wouldn’t have lasted as long as newer cars.
Most OBD1 and Every OBD2 car i've ever worked on had a knock sensor which is basically just a microphone on the engine block, you can pop the hood while the engine is running and give the engine a light tap with a wrench and you will hear the idle drop because the ECU will pull timing, All ECU's do is advance timing until it senses knock then retards timing back down until it stops thus getting the best ignition timing possible. Nothing special or new.
"No SAAB 9000was getting 310 hp *stock*..." Did he say stock? No he didn't.
Paul Taylor too bad GM killed the SAAB.
Yes @ 310bhp the B234R is at Stage3. My point is, a stock engine will run at 1.4 Bar boost with no Knock when using higher quality fuel.
FYI: The above is a just a remap. A B234R can be taken to 500bhp on a completely stock engine. They are fully forged from the factory so dont need to be touched. ALL Stock hardware goes to 310bhp. Then you just change the turbo and injectors and head for 500.
good video. what i like about Toyota hybrid system is that no matter how hard i drive it fuel economy stays good. it's really incredible - the combination of naturally aspirated engine and regenerative braking makes for a system that pretty much doesn't care what your right foot is doing - it always returns the same good fuel economy. of course some people may dislike the feeling and sound of an e-CVT but to have responsiveness of a V6 with over 40 mpg in real world driving - i'll take it.
Ecoboost engines at least in the trucks get worse mileage and can't tow as well as a typical v8. Ecoboost are only good on paper
I’m struggling with the fuel economy with the 1.5L ecoboost in my fusion. If I’m going for fuel efficiency I have to barely use any throttle lol.
Wow so basically when you are driving under normal highway conditions turbo 4 cylinders get great fuel milage but when you floor it to make boost/horsepower they make bad fuel mileage.... Surprise!
My 2019 Jetta with a manual seems to do better mileage wise than expected with a 1.4L Turbo. Rated at 40 mpg on the highway, I've done a 45 mpg trip, recorded by the cars computer. Still fast enough to punch it on the highway as well, doing zero to sixty in about 8 seconds.
That's why I drive a twin turbo v12
Dexter Sullen 'TRUTH' what do you drive?
Vlad Lelcu sl600
So... You mean biturbo?
sorry bud but I don't think your sl600 has a biturbo v12...maybe a N/A v12...but zero turbos on that old crap
This comment makes no sense. Same exact problem happens in any turbo fed engine, whether sequential or twin or single turbo v12 or v6. Problem is manufacturers are pushing engines to do more with less volume.
Reminds me of all these 1.4 liter turbocharged 4 cylinder engines that are in the Chevy Cruze etc. Makes you wonder how efficient they really are.
StrangeClouds there're actually not that bad but it all depends on the location. Like weather, hills, etc
StrangeClouds they're not. My wife has a 1.5L EcoBoost powered Fusion SE
Nice car, a little bigger than I prefer but I swear on everything that I hold dear, I have watched the Fuel Economy hit 3.5 MPG when burying the throttle.
For being a larger "mid-sized" sedan, the 1.5 does pretty well and perhaps in a small application could be a really fun engine but at times I'm certainly reminded that it's not my older Legacy GT. Though it is leaps and bounds more "Luxurious"
Owning a Chevy Sonic that has that same 1.4T. Its everything it's cracked up to be. I get 32-34 average with mixed driving.
StrangeClouds Well... 1.4/1.5 still decent size, in Europe is plenty of 1.0 3 cylinder turbo engines, not only for small but also midsize cars...
i owned a cruze and with that engine got 32 city and 37 highway so not bad and it was fun to drive thanks to the turbo and i live in a mountain state
This is a good explanation of why fords eco boost had valve carbonization issues when used under load. The rich air fuel mixture used to cool the combustion space resulted in incomplete combustion allowing soot to build up on the exhaust valve and eventually ruining the valve and it’s seat
If you drive like a street racer and punch the throttle all the time, the boost is always on = bad fuel economy. I manage to get 6.5L/100km average on a 200hp 2.0T engine all the time on a small hatchback, so not impossible.
Trades46 i do 19,5 liters per 100km average. Wooha lol.
That is really good for 200bhp, you do mostly highway driving?
About 80% highway I would say yes.
I average 7.5l/100 km on my 1.2 TSI 110 hp ahahaha
6,5l/100km city driving, 6l highway, 12/15 track (1.5t chatch)
I don't know a lot about engines, so don't flame me, but would adding an intercooler fix the problem of engine knock in this scenario rather than relying on the rich fuel mixture to cool it down?
AERO BLKHWK32 I think even though ur using an intercooler, the amount of air in the cylinders is much higher and as a result the pressure is much higher. So, as pressure increases, temp increases........even though you are supplying cooler air.......
AERO BLKHWK32 Yes. An intercooler (if there's only one turbo, technically it's called an AFTERcooler) reduces knock. Video explains what happens when boost arrives and the ecu increases richness to protect engine. Premise of video is that we all spend >30% of our driving time with foot on floor. In most countries, this is drivel, as your drivers license will be gone before the contents of your fuel tank. Most driving is done with 0% to 15% throttle. Happy place for turbo economy.
Even with same intake temperature and compression ratio, as there is more air (denser) it heats up more when being compressed in the cylinder.
you can only cool it down so much
He didn't mention it in this video but there is nearly no point running a turbo or compressor without intercooling the gas before it goes into the engine. Also the rich fuel mixture is there to cool the turbo mmainly at high rpm (we are talking about 800°C instead of 950°C+). We made some tests on the engine-bay and as we excellently forgot to turn on the "rich fuel mixture for cooling" in the software, the Turbo-Temp *quickly* went up to 850°C, 900°C is the absolute maximum that system may reach and that is rather over short times.
The knock is a different problem to the overheating turbo that is cooled by rich fuel mixture. Cooling the exhaust gases before the Turbo with a intercooler is not easy and shall not effect the efficeny of the Turbo. VW has a watercooled exhaust connector to the turbo that tries to reduce the need of rich fuel mixture. EE already made a video about that thing.
I baught last year a 1.0 TSI Skoda Octavia 115 hp, 200 Nm. I am verry happy with it, i don''t drive it fast until the engine oil gets to 60/70 degrees Celsius, i got an average of 5.8 L/100 Km till now, and that is excellent. It has 1150 KG without the driver, so the weight ratio is 100 HP/Tone which i think is enough. If people learn how to drive a gasoline turbo engine, everyone will see that is more efficient and fun to drive then natural aspirated gasoline or diesel engine(in my opinion).
ANY engine with forced induction will be less efficient when under boost when compared to operating it during low idle and cruising conditions.
They are extremely efficient. My Jetta gets 42-48 mpg on the highway depending on how fast I drive. In the city it is around 30 mpg. The car goes from 0-60 in about 8.5 seconds. I couldn’t be happier with it. The only problem with the TSI engine is that I will have to get a carbon cleaning in about 60k miles to keep it in top shape.
@Engineering Explained, your explanation is partially correct, a modern Tcharged engine is efficient at low and high loads, first way to reduce engine knock in modern forced induction engines is EGR valves, secondly water cooled intercoolers. I've driven 1.2 TSI Vw group car for 60.000 miles(company car), city, highway and mixed cycles, it got way better MPG then a naturally aspirated 1.6 MPI(equivalent power natural induction engine), both having around 100hp,
Also the fact that non-turbo engines also use richer mixtures under load/to create power.
I got a 2020 Honda Accord with the 1.5 liter turbo. Makes almost 200 horsepower yet it still gets about 42 mpg on the highway
I used to drive a 2012 Buick Regal GS with a 2.0l Turbo LHU engine (manual). It would regularly get 23 mpg as I drove to work. I bought a 2018 Mazda 6 with the 2.5l turbo a month and a half ago, and now I typically get 35-37mpg on the exact same route. I know the 2.5l is tuned very differently and it's a lighter car, but still even for those numbers.. Mazda's real world tuning is legit for my use-case.
DomitionX it depends a lot on the manufacturers because they all default different heat sources by using extra fuel, some of the newer engines use water injectors for cooler temperatures during combustion which requires less wasted fuel to keep the temps down. Also several newer transmission setups involving many more gears allows for cruising at higher speeds at very low rpms which produces much better fuel economy. 9 gears vs 4-5gears lmao what a big difference it makes
I used to drive the "turboed" vehicles back in the 80's (yes, I'm old), and it was the same deal back then -- you had to stand on the gas to get any power. Seems not much has changed since then.
The technology has changed for the better with more efficient turbo designs along with better cooling. But the main principle is the same. They're still a blast to drive but will drink fuel like an alcoholic when you put your foot down. They are designed to do this not only for the demand for more power but to richen the mixture so you don't lean out and fry pistons.
One of my favorite turbocharged vehicles is the older Porsche 944. Primarily gutless but had power when you needed it. Not to mention, one of the easiest and smoothest manual transmissions I've ever driven.
You should do a video breaking down how a e10 blend should not be running a 14.7 like a normal non ethanol engine.
Interesting, I have a Fiesta ST that is supposed to get 26/33mpg with a combined at 29 according to the window sticker. 15k miles later Im at 29.1
Spencer Forman mine should do 14.9l per 100km. I get 19,5.
You should have got a diesel then because you're not using any of the ST under that hood.
When I was leasing a turbo was fine. Now that I own, can’t go wrong with a nice large displacement natural aspirated engine. Mazda 2.5 L Skyactiv 4 cylinder here.
Just up the octane level of the fuel to get rid of knock.
Direct injection can reduce knock, because it waits to squirt fuel into the cylinder right until the piston is almost at TDC. Modern direct injection also has port injection to clean the intake valves and prevent carbon buildup, but the port injection can be used under light loading conditions where there shouldn't be any knock.
Might as well just go diesel/.
Jess Stuart Which engines use this set up?
corvette c7 zr1 and new ford's coyote
@@siraff4461 ford ecoboost 2.7 and 3.5 use it also.
Boost is life. Fuel economy can remain an afterthought. 😎
eM BOOOOOOOOST. It is so addictive man.
Best invention ever.
Until gas prices go to $10/gallon
Arthur Sutherland it is allready here though. 1.80 euro per liter shouldn't be far of i think anyway.
I have a question : Couldn't a solution to this problem not be that the Turbo has to come on later/higher on in the revband ?
What I mean by that is that the small engine, by low loads, would run under the point where the turbo is actually active, preventing knock and allowing less fuel to be needed. Typically, with modern gear systems, you could imagine having the car at a constant 1'800-2000 rpm highway, and when you need the boost, simply drop one or two gears and the turbo kicks in and you have the power for those, in general short, load scenarios.
The shape and mass of the vehicle determines fuel mileage given an appropriate engine size range
i have a GM 5.3 L V8, tuned, with DOD turned OFF and i'm averaging 9.8 L/100 km highway 13.8 overall. very happy with it.
as a "proud" 4b11T owner, can confirm the engine has a compression ratio of just 8:1, is slower than mobility schooter when below boost threshold, and gets 15L/100km or worse fuel economy. all that just for them 22psi factory boost (28psi on evos). glad technology has moved on.
I have the Hyundai version of that engine. Can confirm, not efficient at all.
Max Castillo isn't Hyundai using 4Gxx?
That's why for example older Evos and Subies have ridiculously high fuel consumption. Rather big laggy turbo, high boost figures and low compression ratio. So most of the time you drive it like a N/A car because the turbo hasn't spooled yet in normal driving conditions but you give it more throttle because it doesn't move with it's 8:1 compression ratio and isn't efficient at all...
Discoloured Buttflaps
4B11T is different from a 4G63T
Discoloured Buttflaps, i was able to get 9.5L/100km out of my 2004 Chevrolet Impala, but on the other hand i was able to watch the needle on the gas gauge go down when the gas pedal and carpet were best friends lol
Thanks for that. I could never figure out why most 4 pot turbo bangers with around 250-300 bhp used more fuel than my S54 inline 6 with 350 bhp.
Only time a small 4banger turbo gets better mpg than a 3-3.5L V6, is when your in bumper to bumper traffic. On open roads, your gotta rev up the 4banger turbo alot more to achieve the same speed. Therefore using more gas, the turbo is dumping more heat in ur cylinders.
My friend and I have the same exact cars the only difference is the engine. He has 2016 Ford Escape with the normal 2.0 4 engine and I have 2016 Ford Escape se with 1.6 4 turbo engine. I not only get better hp and torque especially at lower rpms and better fuel efficiency than his engine with more displacement but no turbo. I have seen it the other way where they still get more hp and torque but worse efficiency a lot worse
And the 1.6 escapes engine bay is a sea of hoses & lines. Even changing the oil filter is a PITA
TheeJoeyLee yea it is and there a ton of plastic covering the engine like most cars. I don’t know why companies do that. I always like the look of an engine. I never liked all the plastic they put all over. I know it protects from dirt and stuff getting on the engine but more often than not they are a huge pain getting off to do work
How to downsize an ICE: E100 Ethanol, low inertia turbo, variable compression (infinity), direct injection, plasma ignition, colder spark plugs. That is the way.
E 100 eliminates knocking, low inertia turbo performs better in small exhaust ports, variable compression extracts the better efficiency for every fuel (TRUE FLEX) and every engine demand, Direct injection for efficiency, plasma ignition for faster burn with less advance and better cold starts, colder spark plugs to drain out combustion chamber heat...
Electric cars are not necessary...
sounds like you want to drive your laptop
I’m averaging 35-40 on my 1.5t civic depending on the season. Pretty happy with that
So what's the minimum displacement to gain efficiency from turbo?
Anything more than 0. It depends on the situation.
there's not an optimal number but optimal displacement seems between 0.4-0.5 liter per cylinder
It depends on the size of the turbo, both the hot and compressor sides, and you're operating RPM range. Put too big of a turbo on a small engine and it wont spool it up. Put too small of one on and you can over spool it requiring waste gate or blowoff valves, and then you can compound the problem by constricting the overall exhaust flow.
Size your turbo for your engine's displacement and operating RPM's.
Knock is not from two flame fronts, multi-plug engines have mult fronts. Knock is from the hotspots you mentioned igniting the fuel charge before the piston reaches top dead center so the explosion force is applied to the piston while it is still travelling up.
Mazda Skyactiv for life.
budak lapaq amen
I might buy one new, despite my hate for dealerships
Those variable compression engines are extremely complex and has a lot of extra parts. Long term reliability will be interesting.
Toyota atkinson cycle hybrid even better.
Nick Caesar pretty sure that's Nissan, not Mazda...
I don't know why, but in the game Automation I find it very addicting to make a turbocharged 1.1L i3 engine that revs up to 9100 and has peak power and torque at 7100 rpm. It has approx. 240+ hp.
2017 Chevrolet Malibu. 1.5L , When I set the cruise control at 65 I normally get around 43-47 on the highway. Now go to to 70-72 around 36-39. Having the A/C on “eco- car shuts off at red lights with A/C on.”will bring it down about 6-7MPG less city and highway. So far reliable! 73K.
If I understand well, more fuel is injected for cooling in the same way you spray your face because it's hot outside ? Why not directly spray water inside the cylinder, so it bring down the temperature without wasting precious fuel.
It is rare that I read or watch an automotive pundit that has a complete comprehensive understanding modern 4 cycle combustion theory. Even in the trade magazines. Very good! (ASE Master Tech, 31 years)
Most people don't know about the acceleration enrichment load cells in the fuel maps.
I can say right now that my turbo v6 in my 4x4 F-150 gets WAY better MPG than my old F-150 with the 2wd 3v 5.4 v8 in all conditions.
Trey K the 5.4 is old ass technology. Even the new 5.0 with twice the power gets way better fuel efficiency
Smurfeco 2.3 twice the power?? The 3v 5.4 made 310 hp @ 5,000 RPM / 365 TQ @ 3,500 RPM. The newest 5.0 makes 395 HP @ 5,750 RPM / 400 TQ @ 4,500 RPM. Don’t forget that the Ford GT used this engine (modified of course). The block has been proven to make over 1,000 HP reliability. Look at mustang tuners. The new 5.0 only makes 10% more tq but at 1,000 RPM higher than the 5.4. Also, when using E85 the 5.4 made 395 tq.
Trey K I was just trying to say it has way more power in the mustang and gets better fuel economy I didn’t mention specs how they were cause we all know the 5.0 is a better overall engine than the 5.4
The 2.7 ecoboost outperforms the 5.4 for sure.
Trey K have a 2.7 eb and love it. In sport mode it is a beast
I'm not an engine optimization expert but it's always struck me as odd nobody has explored water injection more.
Water methanol injection is huge aftermarket.
Snow performance.
Aem. Ect.
Had VW Golf 1.4 TSI and it was really economic. More than 1.6, 1.8 and 2.0 last naturally aspirated cars I had.
And of course, even for 1.4 it was so far more powerful. Didn’t got the point 🤔
I had a 2000 Jetta 1.8T, I took excellent care of it, but my best mileage was 26 mpg, worse than that was that over 80,000 miles, routine maintenance and lots of problems, costed over $6,000. Our new 2017 Camry 2.5L naturally aspirated 4 cyl. is getting 35 mpg.
@xHarux3 The Jetta was driven on the highway about 85% of the time, and only floored to pass on two lane roads.
Savagegeese says "you can have ECO, or BOOST, not both"..........
A turbo with inter cooling can also compensate for low density air at high altitudes. Also Toyota/Lexus has the D4-S which uses both port and direct injection which solves some of the issues.
I get better fuel economy than what the sticker says in my 2017 civic SI.
@E5m What you need to understand is the MPG rating was reformulated in 2008 to reflect cold weather starts and higher speed highway driving, hence, the maximum 55 MPH limit to 65, 70, 80 MPH, on so on. Most vehicles lost a 2 MPG rating from the old MPG figures to the current one. Besides, the city/highway numbers show small numbers ranging from low to high with the large numbers being the average. For example, a 6.2 SS Camaro 6 speed gets 16 city, 24 highway. City MPG might say "13" low, "19" high with the big "16" being the average. Highway MPG might say "21" low, "27" high with the big "24" being the average. Then the 16/24 is calculated with 19 being the average between city and highway MPG. The new MPG formula reflects closer average MPG, the OLD MPG formula reflected an average best, but even that can be exceeded by absolute, 100% perfect conditions. Believe it or not, traveling 3 car lengths behind a car in front of you can artificially raise fuel economy due to less wind resistance. Behind a large SUV, MPG goes even higher. Behind a large semi truck, MPG goes even higher.
what about diesel you only reffered petrol engine
In diesel engines, fuel auto-ignition is the goal (diesel engines don't have sparkplugs). It's not a problem, it's normal.
For petrol it's a problem because the fuel is supposed to be ignited only by a sparkplug and nothing else.
VW has a compact car for the Brazilian market, called UP TSI. It produces an amazing 110HP with only 3 cylinders and 1000CC of displacement. The turbo works with some 28PSI and it is considered the most fuel efficient car in production. Hard to determine efficiency when the driver's foot is what makes the difference at the end of the day (or when the light turns green!).
I now live in Costa Rica and I have big ol' American Suburban where most Ticos have small 4 cyl engines. This region has tons of hills and mountains. My big V8 gets about the same MPGs as their cars but I can carry 8 people plus a horse and a dead cat. I rev about 1,500 going up mountains while my in-laws small 4cyl is at about 3-4k with four people.
My Mk 7 GTI once returned an impressive 42 mpg driving from Bend, Oregon to Portland, Oregon. Mostly fast-ish, sweeping roads, a decent amount of climbing, and I was stuck in, "stop/start, slow to a crawl" traffic for a good 10 miles. I didn't think it was real...but it was.
How to save fuel: mid 90s sedan 0 to 60...ok at 10s. 2018 f150 4x4 that can tow 9000lb and weighs 4500lb for your whole family...journalists say it's slow unless it can do 60 in like 7 second. Europe saves gas by downsizing on weight and power. We want cake and ice cream and gummy bears
Exactly. In america our vehicles & us need to loose some weight. Ridiculous how we have to carry 3-5000 pounds of metal plastic glass,& rubber with us every where we go. Perhaps we need more Personal Electric vehicles on a smaller separate road network like a bike trail,(or modified bike trails) to avoid collisions with heavier vehicles.
murica still call an 8's car slow because is not safe for merging on highway despite lower speed limits lol...
American roads should be quite straight and wide so they do need more power
I have the 1.0L ecoboost in my Fiesta and I have a lead foot. The turbo kicks in at around 1500 RPM because the turbo is so small, meaning I am on boost almost all the time when I am not cruising. Even so, I am still getting over 40 MPGs. My milage is almost exclusively highway, so even though I am flooring it all the time when I can, my lead foot makes little difference because of the time I spend cruising. I also drive 5-speed manual if that helps. So for me, it is kind of hard to tell what my milage would be if I did exclusively city driving with constant starts and stops.
Technically, you can get around the need for richer fuel:air mixtures by installing water injection, but this adds a lot of complexity
Thanks for explaining what I have noticed with cars I have owned/own. My current vehicle (small turbo) gets poorer mileage than my previous model of the same car (larger non-turbo).
2022 Tiguan here. I always beat the EPA numbers handedly. I get about 28 around town and 34 on the highway eve at 80mph. The small turbo by them is great, but I'm not willing to bet on other brands.
If I want econ I'm getting a I4 diesel or a hybrid. The other thing people forget if they are trying to save money specifically at the pump is that a turbo charged engine needs premium fuel, not regular. So anything you might have saved by running a small turbo I4 like a granny is lost by the cost of the better fuel.
At high boost there also lack of expansion displacement. A lot of energy out of the exhaust valve.
Which goes in the turbo, which converts it into intake pressure.
I have a 1.0l TSI 3-cylinder engine in Škoda Fabia, my long-term consumption is around 5l/100km (47 MPG) - I consider this to be acceptable consumption for a small engine. When driving on the highway at speed 150km/h (93 miles/h), the current consumption is 7l (33.6 MPG).
Love your videos sir. Facts supported with evidence. So rare and very much appreciated. PLEASE keep it up!
My Honda Civic 1.5t is insanely efficient. Runs lean with no boost and gets 50mpg with a light foot. But yes, if you use all 170HP, you get that relative economy. Honda figured it out. I suspect the turbo location (integrated with the exhaust header) and some enhancements in head and piston shape make it work.
I went from a 1.5L Yaris (solid 5.9LPH) to a 1.2L-T Fabia. The Fabia can occasionally get down to 5.0LPH but any sign of traffic or high load and the economy dies. Also bear in mind it is infinitely more complex than the Yaris ie: turbo, liquid intercooler, regen alternator, idle stop, higher octane. I'm not convinced a small turbo was the way to go it is a bit more torquey but that's it. Great vid.
Two Spiralmaxes in the exhaust and two in the intake. With A drop-in K&N air filter. I get better MPGs than the NA version of my car that has the same displacement. I also have AWD...
Moral of the story: for the common person, who bought a car with a tiny turbo'd engine looking for fuel economy, limit throttle to 50% and never go higher.
Or you could use e85 and eliminate knock throughout the entire powerband and rev range.
In other words, diesel is better.
My Lexus RC 200T does great. 25mpg around town, 31 mpg highway with cruise. Unless I keep putting my foot in it.
You are correct, good information.
Thanks
We had a 2016 equinox with a 2.5 four cylinder that I could get 36 mile per gallon on the interstate and turnpike and around 22 around or home. Our new 2019 equinox has a much smaller 1.5 turbo charged engine. It does get a little better around our house, about 29 mpg, but worse in interstate turnpike driving about 34 mpg.
Perhaps you could investigate power point for better presentation results.
I always thought that they could combine gas and diesel with a spark plug to ignite a tiny bit of gasoline injected on top of the diesel fuel, as I thought the gasoline would ignite better. Apparently you seem to indicate that the science works differently than my intuitive reasoning. So very interesting indeed.
My 1.8T Golf has just over 100,000km on it. I live in Calgary, Canada, so we’re at a pretty high altitude.
My car has gotten 7.8L/100km combined since I bought it. On long highway cruises, it gets between 5-6L/100km, and in rare occasions can touch 4.9.
Is it efficient during city driving? Not really. But there isn’t a non-hybrid vehicle available that is.
Turbos are awesome.
My 2014 Audi A6 2.0T with APR Stage II begs to differ.....Great MPG and most certainly spanks a lot of V6s out there.
"Great MPG" means nothing. Give the actual number and we'll decide if it's "great."
@@wiredforstereo That certainly depends on how I drive it, what mode the car is placed in, such as dynamic, comfort, etc.., It really depends on mood I am in. What numbers are you specifically interested in, without having to pay for dyno..? Off the top of my driving very conservatively prior to APR II I avg 23-24mpg after I easily get 27-28mpg city. Driving moderately aggressive prior to stage II would be 18mpg avg.. after stg II its been 22-24mpg. Driving very aggressive I have seen it between 16-18mpg depending on traffic. So to me with this sports Sedan with Quattro (AWD), Yes it is "great".
@@cyb3rcub My naturally aspirated Asian sedan gets 35 mpg and has 300,000 miles. The only way I get mileage like yours is when I'm towing a camper. Different goals I guess, but 24 is certainly not "great MPG" in my book.
@@wiredforstereo 300k Very nice! What car is it as I can't imagine 35mpg in city driving conditions at all?? If I did not have stop and go traffic this bad here I know it would be higher. Not 35mpg but more around 28mpg. Now highway mpg is another story then yes 32-35mpg.
@@cyb3rcub 05 Corolla, 1zz-fe engine. If I drive slower on the highway, I can get 42+. Have clocked 52 with a strong tail wind. As low as 15 pulling a heavy trailer.
The video is correct, in short OEM's are computing fuel economy based on "real world" driving tests that rely on the drivers "not" engaging the turbo. It's actually been proven that larger V8's can get better economy because you do not have to constantly rev the engine to get the needed power.
How are pumping losses lower? Pumping for more power is harder in a smaller engine with smaller/less ports.
Most of the benefit in a turbo is that the air can be cooled after compression. Compression makes engines more efficient, lower piston compression means more turbo compression. Power is limited by charge temperature compressed at TDC. So Turbo compression is less limited, and bigger intercoolers can mean more power/less knock is possible.
The idea is that fuel economy comes from partial throttle, and overfueling is applied at full throttle only. Nothing wrong with that being under control by the driver.
You can also use water injection instead of fuel, or to make your intercooler more effective, but everyone likes the popping and banging of overfuelling.
When I had a fiesta st, it would do fine cruising on the highway and around town as long as it was flat. If I hit even a moderate hill, the engine would dump fuel because the turbo was in its power band.
I’ve got a 1.4 liter turbo Jetta (2017) - It gets 40mpg on the highway, 0-60 in under 8 secs, and usually 36mpg around town. I’ve yet to have any problems with the car. It has the room of a midsize, the acceleration of a v-6, the economy of a subcompact. I’m not sure how you can ask for much more from a cheep compact car than that ($16k new in 2017).
Today I drove 500km with Opel Crossland X with 1.2 turbo threecylinder. It was mix of 40/40/20 highway/ countryroads/city . My fuel economy was 6.4 l/100km that is around 37mpg which is very good. Engine has 81kw and feels faster then my 318i 105kw bmw.