Does a louder exhaust make more power?
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- Опубліковано 2 жов 2024
- It's a question that's full of controversy so today we ask an expert: Does a loud exhaust actually equate to making more power?
Dyno testing a potato in an exhaust pipe • Increase HORSEPOWER wi...
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/ tunedbydale
Damn, Dale's dropped some serious weight! Great work mate
Came to say the same thing, He looks like he's doing good.
They always say losing weight is easier than increasing HP but I think it really sucks.
thanks mate!
I really wish homeboy wouldn't have said backpressure at 2:40. Scavenging and backpressure are not interchangeable terms. Scavenging creates a vacuum. Backpressure is just pressure in the wrong direction. They're literally opposites.
Yeah I was thinking of the same thing. We don't want back pressure! Instead he should have said that going to a larger pipe diameter begins to reduce the flow velocity.
@@headchef5680 bingo! It's not a pressure thing. It's a velocity thing. It's not even a scavenging thing once you get past the header collector.
dale says restriction hurts power but then says you need backpressure. what you actually need is gas speed in the exhaust and that creates the scavenging and thats why bigger isnt better
100% Dude knows that it's really about velocity, but for a simple explanation video he's going to get the main points across to 99% of the audience at the expense of having a few anoraks go "he should have said velocity instead of backpressure' in the comment threads lol. and to be completely pedantic, scavenging is an outcome, it doesn't create a vacuum. the velocity differential between the exhaust impulse and the other headers is what creates a vacuum, which results in scavenging. I'm surprised nobody in here is also talking about harmonic resonance and it's impact on reducing valve float - I'm not an expert but the guy I worked for was, he had the science down to an art (his words not mine lol).
@Ewing Fox I disagree entirely. 99% of the people who watched this walked away thinking an exhaust system needs backpressure thanks to him lazily interchanging radically different terms. I hear it ever single exhaust conversion: "yOu nEeD bAcKpReSsUrE..."
I don't care how fast dude's car is. Backpressure is NOT needed! The end. Been proven a LOT on the dyno. What DOES matter is primary tube length and collector length...both of which affect the scavenging through the pressure waves (which is where people get the whole backpressure misconception from).
Yeah, this. As soon as he said lack of backpressure all the people that actually know left the chat, or came down here to say that.
From what I've seen: the louder the car, the slower it actually is. People are trying to sound fast, but without putting in the effort to actually go fast.
True, i have no cat, no muffer only resonator in my car and thr car is still pretty slow at around 5.5s 😂though i think the volvo i5 sounds decent.
In fairness with modern small engine cars there's very little in terms of basic mods that can actually make any positive difference. These things have been optimised to bits, a serious and educated re-map might open up more at the expense of fuel economy or long term reliability, but realistically the stuff that's on the engine is there because it's right for that engine. At this point if you want to mod and make a real power difference you need to get your hands REALLY dirty or open your wallet, probably both.
Poorly designed headers are going to be your main concern. Aside from that you just want to avoid having massively oversized piping that will slow down exhaust velocity.
Velocity is directly linked to pressure, if it's coming out at speed then it's under pressure and it's under pressure because flow is being restricted. Again this always comes down to NA vs FI, if you want to get every last bit of power out of an NA you need to balance pressure with flow in order to promote scavenging, if it's FI you just want to get that gas out of the way once it has passed through the turbo
this is really funny, this video appeared as I'm looking at full system exhausts for my bike
5hp per 10db added. Similar to stickers, but better
Explains funny cars..
@@Zepplin76 😂
The gospel according to Hd lovers.
Put a pressure probe on the exhaust close to the header. You will find that no properly tuned engine "likes backpressure". Yes, scavenging is a thing, but that is mostly dictated by your headers, not the rest of the exhaust. There still is too big of an exhaust, not because you want more flow resistance, but because bigger doesn't always mean less resistance.
If someone needs to know about unicycles, then you’re the man but until then; keep your engine tuning “knowledge” to yourself, you’ll look less thick…
@@tom6493 looks like I know more about both unicycles and engine tuning than you..But if you are so smart, explain to me why backpressure in the exhaust can be good.
We used to build turbo cars that had supertrapp exhausts - some circuits required lower noise thresholds so you can add plates and meet the requirement - remove plates, or pull the stainless steel sewage diverter valve and dump straight out the bottom. Turbo car awesomeness! With NA cars, scavenging is a real thing - perfect example was a 1986 Audi 4000 Quattro that I bought off the shop I was working at. The muffler had a broken baffle that rattled like a bastard, the shop owner gave me another muffler (900$ at the time for a replacement 😮) but the previous owner had backed the vehicle into a curb, making it effectively unusable. I ended up cutting up the original muffler and installing a $29 Cherry bomb which fit perfectly - both my budget as a broke college student working two jobs AND the rather tight packaging issues getting up and over the rear axle and across the rear end for the where the turnout needed to exit the stock bumper. The downside - I lost power between 1800 and 2,200 RPM, which was the real swan song for those NA 10 valves. I also noticed a bit of roll off at the very top which I attributed to a little bit of valve float that I hadn't noticed prior. It sounded fantastic (to my 20yo ears!) But nowadays - at 43 - I would probably shake my head and call my younger self a dickhead. It got me an inspection sticker so the drop in power was definitely worth the $860 USD savings when I was clearing about $275 a week at that job!
supertrapp is cool, they also make motorcycle and quad exhaust or atleast used to.
more plates = less top speed but more torque. less plates mean more top end, atleast that is what supertrap says ;)
@@reggiexp69 yep, it gets more complicated than that, but it was a simple way to effectively change the velocity of the air in the exhaust and at the time with the really barbaric ECU tools we had at the time, test-n-tune provided a lot of data about what worked best in what conditions. I think the company is still around, they solve the problem at the least effective location - exhaust design needs to start at the exhaust port lol - but it was the easiest to make changes to on the fly. Someday i'll do a retro build and 9/10 it'll have a supertrapp on it :)
I know how it feels to be desperate for attention. I've tried everything, too.
Recently scored a cherry Toyota Corolla - 2003. Straight-piped and totally pimped it.
The babes have taken note. And, quite a few dudes.
Hoping to sew some wild oats. I'll keep the community posted on any success.
One of very important factors is that by replacing your oem exhaust system to an aftermarket you actually reduce weight of the car. Less weight - faster car.
A lot of heavily modified drag racing vehicles have exhaust tips coming from underneath the car. Drone is insane but by removing 10 feet of pipes you are saving another 40 pounds
Not for street cars though, bigger pipes usually means more weight, also stainless steel is heavier than mild steel, You may or may not save soem weight on the mufflers but that is very dependent on specific parts.
@@henrym5889 40lbs from exhaust, 30lbs from pass seat, 10lbs lighter wheels, etc… and you already lost another 100lbs.
When it comes to racing, every upgrade counts. Just chopping off your exhaust is not really going to make a difference or just by replacing your intake same story. But by combining everything together such as lighter exhaust, lighter wheels, tune, intercooler, etc. overall it will make a huge difference.
I’m coming from drag racing and have raced exactly same speced cars as mines but fully gutted (no seats, no interior, cut exhaust…) and they were significantly faster
@@henrym5889 well, what cars are we talking about then? I purposely started this discussion under this video because Marty and Moog are building those cars for racing purpose. And on the track every saved pound counts.
Fabric door handles on the 911 gt2 rs instead of regular handles have been installed on the car not only for “fancy” reasons. Is that really lighter? Not really, mb another 5lbs. But with the combination of other small lighter parts the car performs better on the track. P.s. I’m not a Porsche fan. I don’t know much about them. Just gave an example of a car which is a good performing track vehicle.
You are right 40lbs is almost negligible. But as I stated above, when you are reaching faster track times or better 1/4 times and every 0.1 seconds for you is important (which should be as why wouldn’t you care about it), those another 40lbs from chopping your exhaust out will make a difference.
10ft of pipe does not weight 40lbs.
@@krusher74 just for your understanding how much the oe exhaust heavy, I will give you an example of the axle back exhaust system from a Audi rs3 (including resonators, muffler and pipes). The weight is about 70lbs.
God I was teething at the idea of him going into the depth of the scavenging topic. I'm going to go into a deep dive on UA-cam and the interwebs now. Fascinating stuff!
No sorry back pressure is bad.
Ever heard the saying "the best exhaust is no exhaust"?
Why else do top fuel dragsters only have runners.
Yes having a too big exhaust for your engine can effect gas column enursia, however you want to have as much velocity in your exhaust with minimal back pressure. You need velocity through an exhaust system to get good scavaging especially on the over lap period on a 4 stroke engine. Back pressure does not help scavaging.
All props to "Team Marty", because "why not"!
I cant believe you cock blocked Dale, before he got into his VW Crackle tune rant.. I legit wanted to see where that was going to go...
Oh wow. Fresh MCM
Detail: the chrome in stainless creates toxic fumes while welding. A good SUCTION (there, i said it) of the gasses/fumes while welding is important. I you want to go for expensive (so you have someting to boost about at parties) go for titanium..
Rock on bros.
LOL.. listening to this guy hurts my head spilling out the same wrong nonsense (thats been proven wrong) found at any basic muffler shop
Audi LMP car, racing in the weathertech series was very quiet. And I bet it is faster than your cars :p
The sigh and f on crackle tunes haha. I got a custom 3" Turbo back exhaust for $870 at Idle was 92db so went back and got a different centre muffler as did not want a yellow sticker :) didint like the drone of the center resonator either now 82db idle no drone and quite while cruising but Loud full throttle. Im interested if Hooker Aero Chamber style mufflers increase flow I had them on the Suzuki and have a nice growly note but HEAVEY! I know one fell on my head.
I think a lot of people need to watch this video, including my mate that says his motorbike goes ultra fast when he runs fart cannon style with the muffler cover removed.
He doesn't ride a Harley does he? 😂
Way too many motorcycles like that, in the realm of 2 wheels the concept of louder vs faster is very apparent and even easier to witness first hand.
We fall victim to perceiving speed from noise until you're watching it accelerate from a distance. Open headers on a bike feel fast and sound fast for the rider but stare at the speedometer and you'll be crushed, get a full *decent* exhaust system and even if it's quiet and not feel fast per say the rate at which the speedo needle travels is surprising. Or with your straight-piped Civic have a buddy drive it while you watch and man you'll think he's taking his sweet little time.
what's louder, a straight pipe golf, or a comment bro when he hears the word "back pressure"?
id go for less weight overall if possible and maintain the engineering already present but less general restriction/baffles
Being in an Mx5 MK1 which has a stock exhaust but the backbox has been abused I can say I'm wanting to go back to stock. The noise is stupid. I'm all for nice exhaust noises but it needs to be done properly and have the right car to back it up
Was Dale kneeing down the whole EP or were you guys standing on a stack of Subaru head gaskets?
I have a 51sec car takes 1 seconds to start lol😂
Scavening and backpressure are the opposite🫣
Right! I can't believe an "expert" would interchange those words so inaccurately. This is also the era where boys pretend to be girls and so on, so I shouldn't be surprised.
But my cousin uncle brothers dad from my moms sister side husband ran 15in straight pipe and made 8000 horsepower on his golf R 😂😂😂😂😂😂
If you have to route all the exhaust through one catalytic converter you might as well forget free flowing exhaust unless its a Ford they have two. Its not fair that GM had only one in the 1970s
Can we have a video with Dale explaining scavenging
Totally buying that scanner on the next month or two.
There was one episode of Engine Masters, where they put an engine on a multiple dyno runs changing only the exhhaust, and found that the bigger the pipe - the more power, and back pressure doesn't play any considerable part in maikng hp
That had that all worng, they went from an exhaust that was too small to one that was right, they never tested one that was actually too big,
From what I have been told by a tuner here in Denmark; an aftermarket exhaust system on a modern car won’t really make any real performance gains by itself…..only with proper tuned headers and an ECU remap will you really benefit from an aftermarket exhaust.
Just to be clear; I am no expert and I don’t claim to be either, but that’s just what I have been told.
Dont use more than 54mm exaust pipe in both cars
when we design exhaust systems professionally, to clarify what they're on about re: "backpressure", maximizing flow (via the pipe energy equations, for you nerds) is about balancing two OPPOSING factors. flow rate is fixed and set by the heads/engine, called Q, where Q = area * flow velocity. as you change EITHER area OR flow velocity, it affects the other. if you move to a larger diameter exhaust, the flow velocity plummets; and you can constrict the exhaust to speed the flow up, but that restricts flow and increases losses from drag and fluid turbulence. at some point there is a sweet spot where their total flow is maximized. that is your ideal exhaust diameter.
so no, back pressure doesn't matter. but you DO need to maintain flow velocity, so you HAVE to limit the size at some point. that's what they're getting at in a roundabout way.
what boomers call back pressure is actually "head loss", a term for parasitic losses in things like curves in the pipe, catalytic converters and mufflers, marty's little contorted colon tube, etc. you want to MINIMIZE head loss as much as you possibly can as it results in direct power increase even at the same flow conditions.
scavenging is about tuning the exhaust (and mostly header) length so that the individual pulses out of the cylinders arrive perfectly timed and cause a little vacuum to pull the exhaust out on the next stroke. that (and intakes!) are tuned lengths set by the frequency of the intake or exhaust valves at your target RPM. there is a reflected wave whenever you move from one diameter to another, such as at the collector of headers. you match these frequencies together to get scavenging. headers require tunes to set the timing (and therefore intake frequency) for your aftermarket header length.
things that affect scavenging (such as headers, intakes, Y-pipes) or confuse the MAF sensor require a tune to make power.
things that reduce head losses (ie, cat delete, intake air FILTER) will show immediate power improvement and do not necessarily need a tune, but they will make even more benefit with one. this is because head loss exists AT THE SAME FLOW RATE, it has nothing to do with "flowing better" -- remember that the Q flow rate is FIXED by the heads and applies to the ENTIRE exhaust in all locations!
What can I do to my corolla ae101 93 ?
Do you need it no do you want it YES
Likely asking a dumb question but (here it comes) why not design it like a trumpet to "tune" specific notes? I mean Yamaha was involved with their music knowledge for LFA?
You could, but you'd need an engineering degree or access to software to map the sound waves. You can't just make a trumpet shape and expect it to have a "tuned" sound.
They design the length in resonators to tune specific frequencies out (ususally to eliminate drone at cruising speed), which in a way is similar to how instruments do it. If you mean why they don't make it trumpet shaped, that is because the space available doesn't really lend itself to it. It's not the bends that tunes the trumpet, it's the length and diameter of the tube, the bends are only there to make you able to hold it in your hand.
Back-pressure is the wrong word, very arbritray in its meaning and understanding by the car community. You want to balance size and velocity (aka scavenging as MCM put it) to get the optimum power out of an N/A. It's actually easier to get a tried & tested off the shelf exhaust system for an N/A, boosted cars on the other hand, custom 3.5 or 4inch straight through will be fine.
What a load of BS. "Back pressure". It is atmospheric pressure, it is 1 bar no matter the diameter. It makes no difference and it is not needed for the engine.
Hot civic owner logic - remove muffler put on fart can, keep catalytic converter = louder car = more power. In reality maybe, maybe 1hp gain. High resonator + high flow muffler = butt dyno horsepower.
Strictly speaking noise is like heat. It's a by-product of eneficincy. More heat or more noise is less useful work. That's all things being equal though.
I've never understood why people put so much emphasis on the need for "backpressure". I understand acoustics as a sound engineer (+car mechanic), and it kind of makes sense that you can "reverse scavenge" - sucking on the exhaust valve right before it opens to produce vacuum at the exact time it needs to evacuate itself. However, what most don't realise is that in any tuned (resonant) system, there are usually only certain frequencies where this occurs efficiently and effectively. Depending on the Q-factor of the system, it'll only scavenge exhaust gases effectively in small parts of the rev range.
It's like those tubes you whirl round as a kid. They make tones only at certain frequencies based upon their length. Same with resonance in the exhaust system. Only certain rpms will produce better flow due to vacuum in the exhaust coinciding with the exhaust valve opening. But still, no real extra flow as there's always going to be the acoustic pressure coming back the other way in roughly equal amount straight afterwards. Sound waves go both ways, not one-way.
IMO exhaust "back pressure" is a stupid idea someone got into their head one day and it seemed to stick. It may help in induction in the intake at certain rpms, but not in the exhaust, where all types of restriction are counterproductive. What goes in must come out.
To those who remove exhaust restriction and their power reduces, I'd say this:
So long as you can tune the ECU for the inevitable changes in the exhaust flow characteristics (which affect volumetric efficiency), reducing back pressure is only a good thing. You WILL gain more power - IF you retune the ECU to deal with the fact you reduced restriction in your exhaust system.
In addition: My brother's motorbike had a less restrictive exhaust on it. It dramatically reduced its power. I "tuned" it by changing the needle position in the carburettor. His bike had a ton more power after the restrictive exhaust was replaced with a less restrictive (and louder) one. There's no way he could've had the same power if I'd done the same carb mod while the restrictive exhaust was installed.
Hope this helps people to understand that the so-called _"requirement for back pressure to produce more power"_ is absolute nonsense. Back pressure comes first due to exhaust limitations (govt. noise regulations), and engine designers need to tune their engines around it to make the most power they can with the exhaust flow restrictions. When that flow restriction is removed, it changes the characteristics of flow, so the engine suddenly doesn't work properly. But once tuned, it will work MUCH better than before.
The Motortrend show Engine Masters proved you right on one of their episodes using an N/A engine no less. IIRC, oversizing the exhaust system never caused a loss of power over what anyone would consider "stock" and they only ran into a case of hitting a plateau. After a certain point you just stop gaining power. And unlike this "expert", they had the dyno charts to prove it. They also completely debunked the whole backpressure nonsense.
What I'm about to write applies to NA engines. Once you bring turbo-charging into the mix the parameters are different. With that said I'll continue.
Years ago I took my hillclimb/time trial car (it was a Gemini) with many engine mods including a 3 inch exhaust and detuned it to put it back on the road. Took the twin webers off, changed the cam to a more conservative one, and generally tried to make it into a more traffic friendly car, but the 3 inch system remained. A few months after it was back on the road I caught the exhaust system on a driveway and damaged it, so I took it to a shop and had them make me a smaller 2 inch system that fitted closer to the floor so clearance wasn't such an issue (the car was quite low). It was now a road car so practicality was the objective, rather than outright horsepower. I did this at the suggestion of the exhaust shop guy, his exact words were "a bit of back pressure will help to make it more driveable". Much to my amazement the engine picked up power, especially low down. It was definitely more tractable and less "peaky", and improved driving in traffic considerably. Now like you I was pretty sceptical about the whole back pressure thing, and no one was more surprised than me when that happened. It turns out back pressure is a thing, and CAN make a difference in certain applications.
Over the years I've had many conversations with car/engine people, in a motorsport context and otherwise. Making a blanket statement like "it's a load of garbage" is a foolhardy action, because it's not that simple. Every application is different, and what works for one setup may not necessarily be any use in another. It should be approached on a case by case basis. Some engine/manifold configurations respond well when attention is paid to correct scavenging, with others it doesn't make any difference. It's all about which application, and what the end goal is.
By your logic correctly tuned exhaust extractors are a waste of time and money, yet we all know that in most applications they absolutely are not. There are measurable gains to be had by extracting exhaust gases efficiently. If so much attention is paid to the initial exhaust removal process, why then would the rest of the pipe have no effect? The example you cited found it made no difference, but that's just one application, and it's interesting to note there was very little information provided on what the original system was like before it was changed. If it was already well set up then any improvement is going to be a lot harder to measure. There are plenty of other situations in which a measurable gain has been found, mine among them (a car with a carb and no ECU, so tuning adjustment wasn't really an option aside from carb jetting which was already pretty good and required no change).
Whilst it's very true that less restriction is generally better than more, there are examples (and I suspect Marty's Peugeot is going to be one) where you can take it too far. The trick is to match the system to the engine, keeping in mind what your objectives are. Dismissing the entire concept because of one or two sets of results is a bit narrow-minded, especially when it goes against well established and provable knowledge in motorsport and exhaust extraction worlds.
Keep your mind open. The correct amount of back pressure in a suitable application is absolutely beneficial. As I said, I think Marty is about to find that out just like I did all those years ago. In theory (and most practice) a system that flows more freely will help with outright horsepower (to a point), but if it comes at the expense of tractable drive-ability in a road car, is it really better? Food for thought.
Yeah you pretty well hit the nail on the head, less about back pressure than it would be about exhaust gas resonance and the velocity/pressures of the exhaust gases creating a venturi effect on the corresponding cylinder(s) and would only really increase, be beneficial, or maybe even noticeable by monitoring via EGP/EGS sensors at certain rpms where the exhaust gas pressure is optimal for scavenging for the particular size/angle of tubing etc. As you mentioned though there'll always more likely be a flow limiting factor like the valves, cam duration, exhaust port design, etc
@@JimGriffOne the reason for back pressure is valve overlap, and over scavenging. With modern engines the majority of the time both the exhaust and intake valves are open at the same time. The intake charge can and will move out of the combustion chamber and into the exhaust. Meaning less fuel and air in the combustion chamber to be burned, resulting in less power. A great example of this is drag pipes on a Harley v-twin. They ok at a high rpm at wot, but will be flat until you hit the sweet spot.
The louder sound pushes the car more
Dalecnt! /pf
Also Marty’s system will still have some back pressure with that skinny link pipe. Might even go alright!
The success of an exhaust system is all about balancing cost, durability, noise & legality.
We had an Alfa Sud & when it came time to replace the muffler, I chose a totally legal & awesome sounding SuperSprint rear muffler. The sad story was that it rusted out in 18 months, so I went for a stainless steel replacement, but the wall thickness was so thin that it sounded very tinny & not at all like an Alfa should sound.
If I did it all over again I'd keep replacing the SuperSprint muffler & enjoy the bliss of the subtle raspy purr. 👍
@@sinAnon6689 Spot on. I used to intentionally backfire. It would fix it, only to return a day or two later.👍
The car or the exhaust 😂
Bi-Modal mufflers for the win!
Asking this random shit here cause then you can maybe answer it in a unicorn ep
Hey guys do you always wear MCM shirts?
Do you have favorite MCM shirts kept away like a first edition of certain one or hat or something?
What do you wear if not MCM merch?
Be great if Dayle knew what he was talking about.instead of pushing the back pressure myth.
screw the your log manifolds im debating flipping the na manifold they make the best turbo headers
C'mon guys!, You didnt even comment on the street cred you get when you straight pipe a V6 Commodore.
0:18 he's got a 6 second car, comment champs.
Queue the experts...
Loud Pipes Save Lives!
Straight pipes are the only answer.
For those with a Toyota 86 a bigger exhaust helps with the torque dip.
What kind of potato should I use? And should I leave the skin on or off? 🤔
Loud exhausts frighten Prius drivers that alone is worth it
Stainless steel gets hotter than mild steel meaning hot gases will come out faster from a stainless steel system
Straight Through Perforated mufflers are ideal.
I love this series! Especially here on the main channel! The second channel is too mainstream 😊
Delete the cat center muffler run e85 and get big flames
put do the peugeot exhaust mainfold 4-2-1 and this change power from 109hp to 125hp with this TU5JP4 Engine. even a rest exhaust is stock.... MCM this doing BAD.
Always! Don’t even need to see the results 😂
I'm actually interested in what the pros cons are of log and tubular manifolds on both N/A and forced induction vehicles? Anyone got a good reference to check out? Love the cash vs trash series guys
Log = less lag and peak Hp
Tubular = more lag and peak Hp
*Logs are generally tuned for low end torque rather than high end power. Factory cars are trying to fit enough torque to keep people content while minimizing emmissions and package size, log makes perfect sense for that.
Tubulars tend to move the powerband and pulse timing up the RPM range, as that is where you can make bigger HP numbers. Takes some steam out of the bottom end though.
A decent rule of thumb, logs for the street(ie. daily), tubes for the track(ie. weekend warrior).
(strong argument to be made for asthetics as well though, logs are ugly, tubes are hot. The performance difference for normal folk is small enough that your preference is totally fine)
Thanks guys that's really informative I appreciate it
Scott Russell! Mr Daytona!
^ This guy ^ is an epic motorcycle racer! He won the Daytona 200 5 times, won the Suzuka 8 hr, and most superhuman of all, won a World Superbike championship on a shitheap Rob Muzzy tuned Kawasaki.
Hmm, might just turn on some music and cruise
At the end of the day, if it can transport hot, stinky gasses to where they need to be in a timely fashion, and not upset the popo, it's all good.
I'm here for the log manifold madness
got a res delete on my focus st
Formula Mazda NA Rotaries have a 2stroke style large chamber after the header to improve power/torque.
Given that a wankel engine is, by piston engine definition, a one stroke, it's easy to see how that would work.
Tijuana say hello guys....Daniel
Not really. But an equal length primary header. Coupled with an exhaust pipe that is the same diameter as the output flange on the header, and also is as straight as possible with no cat and no mufflers, would theoretically mean maximum flow and therefore maximum power.
It will also be loud as all hell let loose, ask me how i know. 😁
straight pipe isnt actally the best, look into reverce cone expansion sections
@@krusher74 Yup, the cone basically increases the vacuum/scavenge effect right?
But you can also do that by putting a teardrop or cone shaped object at the end of the straight pipe, with the point aimed towards the engine.
When travelling at speed, the vacum created at the flat/rounded edge, by both air rushing by and the speed of the exhaust itself, will cause a slight vacuum in the exhaust pipe, hence aiding with extraction. At least that's the idea as far as it's been explained to me.
It's a lot like the potato mod mcm tried a couple years ago.
Ah, back pressure, the oldest myth.
"a crackle tune, fuck" :D
First car I thought of in the MCM garage was the Mini as an example. Sized to suit and the car and its use = perfect
Cost vs looks
I like Dale
Zoomies!
Noise in my opinion won't improve power,but ask a funny car racer they would say different
🙂
Dole
I've run my NA 2.5 sentra on both 3 inch and 2.5 (it Might be 2.25 inches but pretty sure it's 2.5)
Anyway ran a 15.6 and as low as 15.2 on the smaller pipe with 87 and 10% ethanol. Went back to the track the next year, on 91 octane and 3 inch exhaust. Again ran 15.6.
higher octane means nothing if you dont need it to reduce detonation, lower octane acturally burns easier.
Em wit if t.d? Soz mate
My current car is turbo charged and I felt (sorry but no testing done yet) that changing to a sports cat (200 cell) did make a difference. I'd like to hear others opinions if this is the case. It was tuned before adding the cat btw
its needs a retune with the new cat then
These segments are good for those just starting to mod there cars and gou guys dont just do these mods you actually get and expert in these field to do some explanations keep up the good videos will be interesting to see the final results👍👍👍✔✔
The second he said back pressure, he lost my interest. Anyone who says you need back pressure is just plane wrong.
i installed a flowmaster muffler on my V6 mustang and now its a GT. All my neighbors agree
There is no such thing as back pressure. It's a vacuum that is created that keeps pulling not back pressure you would never want the exhaust to go back into the engine