All turbo & hot pipe blankets are NOT built out of the same stuff & are NOT equal & the most expensive on the market is NOT the best. Silica quilted blankets are by far the best. The goal of boosting an engine is to increase the air density to the engine & hot side heat absorbed by the cold side is counter productive to that. Plus if you're picking up hot intake air under the hood you are also decreasing the density charge. Monitor the charge temp at the engine, the lower the better.
Very informative video Rob, I run a TB on my old v3 Impreza STi. With its top mount intercooler, it would absorb a lot of heat from the turbo nearby. With the addition of the TB, the turbo area is now much cooler but more importantly the TMIC is cold to the touch, they do work.
Jokes aside, melting things like engine mounts and cushion clamps is a VERY real concern when packaging turbos for OEM applications. Been there, done that. IMO, I'd strongly consider a bunch of heat wrap on your down pipe, in addition to the blanket, Rob. If you run it down a ways you may get rid of some of that interior heat too.
Good job with the video. I have one thought. Your shiny intake has a very low emissivity. Meaning that it reflects infrared light. Not convinced the heat you saw in the infrared image was real. Most likely reflected IR light from the turbo housing. You will need to take temps of intake with a contact probe to confirm actual temps.
I would love more videos like these. Quick question, with the heat trapping effects of the blanket, what does that latent heat do to the oil/water that remains in the turbo once it is shut off? Would the blanket introduce an environment that promotes oil coking?
hey since you have a thermal camera how about a similar video comparing stock vs header wraps vs ceramic coatings......maybe even both combined, a lot of people remove heat shields to install headers, heat gets transferred to oil pans and transmissions
Turbo blankets are always good! someone on NASIOC took their thermal camera, and tested blankets/gold tape/and some other items and came out with some good info.
This is why I really like turbo blankets & full exhaust wraps. They protect everything from the heat, and I think they keep the heat in the exhaust system, so the whole system is more consistent, the exhaust flows out better, and doesn't slow down & create some resistance, because of the colder sections making the exhaust flow denser, like the final parts of the straight pipes, the mufflers, or the parts of the plumbing hit with cool air.
Definitely blanket turbos. I work at a petrochemical plant, all of our steam turbines and turbo expanders are blanketed. When you insulate, it keeps the process more adiabatic and closer to the ideal isentropic process.
Literary just purchased turbo blankets and exhaust wrap for the RX7 and GTR today before watching this video,. This helps explain the spider web paint cracking I have on the RX7's hood. Very informative, thanks for making this!
Great great GREAT! Video dahm!... ive just finished a turbo upgrade on my rx7 and have been in discussion about use of a turbo blanket, the one negative that ive thought of is the fact of it holding heat in could produce moisture and also may scortch the oil!?!... great vid
i did a video similar to this last year, i had a lower quality blanket not like one you had, I only at a laster thermometer and you did a much better job than I did, good stuff man.
Less heat also decreases the possibility of engine wear or mechanical failure. To protect the paint on the hood however, I'd just pop a reflective insulation guard under the bonnet where it's meant to be (or run methanol lolz) I will defo second some of the comments below. Get that turbo blanket, wrap your headers and use quality lubricants including coolant. Also ensuring that your custom radiator provides good enough cooling (heat dissipation) for your particular vehicle, is never a bad idea. All this comes down to; if you want your car to perform consistently, invest some time in researching upgrades, save up the bucks and stick to only installing quality parts. Very informative video, thank you @Rob Dahm ;)
Doesn't rising your turbo temperatures kill its bearings faster? I'm affraid that this would kill turbos sooner just like the wraps to the exhaust manifolds do, the temps usually increase the likeness of cracks and deformation due to expansion.
I was thinking the same thing. If your wrap the turbine housing then it cannot dissipate heat to adjacent components. Sure, the compressor and intake manifolds may be cooler but you are adding a lot of heat stress to the compressor, increasing the chance of bearing failure or a crack forming in the housing. Would it make more sense to wrap the compressor housing and intake manifolds to insulate them from engine bay heat?
+Eryk Szymanski your statement isn't wrong, but if you want to use the energy that's gonna be wasted, you must wrap up the exhaust manifold and insulate the turbine, to use as much enthalpy as you can squeeze out with your turbocharger. For sure your thrust bearings need to be cooled more than before... You know, when you talk about performance, you always have a short blanket...it's not simply to have maximum reliability, efficiency and power at the same time ;)
This was my thought as well. Turbo blankets (as has been proven a few times) have a HUGE impact on containing heat, but at the expense of the overall longevity of the turbo. Enough to be significant in my opinion. I'd rather opt for an inside/outside ceramic paint job. I don't think that's quite as effective as a full, thick blanket, but a proper ceramic coating will help keep temperatures more tame while still dissipating properly.
Love love love real world application information videos. No speculation, just hard fact. Turbo blanket or no, this is precisely the reason I'll be going with rear mount turbos. I'm really surprised you haven't as well. I mean, it's out of the engine bay, further time and distance for the air sheathe to cool, easy access and install, No manifold fabrication. Hell, on my OctoRex I've even got heat shielding where the muffler used to be .
because of this video, i just bought a turbo blanket for my wrx. Reason i never gotten one is that theres a hole inside the hood scoop that cools the turbo but the blanket will help during hot summer days in traffic.
I am a firm believer in exhaust wraps or coatings aswell because I have had guys come in complaining of hard starts after a hard run down the road. the cause was the heat from the header or turbo evaporated the fuel in the fuel rail
Yessss plz do more videos like these whenever you have the opportunity! Being able to walk away from a video with more knowledge than I had before watching it is always a plus in my books.
Definitely do more science videos! Performance can be gained using a blanket due to a less thermal energy transfer between the exhaust gas and the turbine housing. A cooler turbine housing absorbs more heat from the exhaust gas (decreasing pressure, temperature and ultimately mass flow) As turbine surface temperature increases , an ever smaller fraction of exhaust thermal energy can be transferred to the turbine housing. This leads to less pressure loss and better mass flow. The major drawback to turbo blankets is a BIG increase in heat transfer engine oil. On a rotary, which has very very high EGT's normally, this could easily lead to oil coking.
Dahm kept mentioning the cost of the Turbo Blanket like it was $1000. I checked out of curiosity and they are only like $50-$150. I thought they were going to be way more expensive. Definitely worth the money for the benefits you get. Excellent video BTW.
One more thing to remember is that hotter exhaust gas has a higher velocity which help in scavenging exhaust out of the turbo and exhaust quicker which also helps turbo spool. 1 more thing to remember with a rotary is that it's exhaust gas is several hundred degrees hotter than a piston engine. Because of this heat soak is worse so a turbo blanket and thermal control is even more important with a rotary. Also the RX7 engine bay is real big so there isnt as much air flow especially when you drop a larger engine than what the factory engineers meant to be in there. A 3 rotor engine will be worse than the stock 13b and a 20b will be even worse.
Would love to see a difference between a bare turbo, ceramic coated turbo and ceramic coated with a turbo blanket. I know the ceramic coating on my ducati's exhaust helped a ton keeping heat off my leg as well as keeping the radiant heat off the parts that the exhaust is near throughout the bike.
I've worked with turbos for the past year at an airplane engine shop. going to start suggesting blankets now for the racers. thanks Rob. would love more!
When heat is contained in an object that pushes hot air, that contained heat helps push it out faster, also keeping the temps around the dump pipe and rear housing the same stops unwanted expending of metals and stops regular flow. It's like driving down the road, and in one area for 1000m its 40 degrees and after that for 1000m is 10 degrees and keeps changing. I have a turbo blanket and heat shield aswell and you can notice the car comes on boost 0.90secs faster on boost and its alot more constant. Next up is Ceramic coating Make a video on Ceramic coat headers, rear housing, dump pipes etc?
presumably any given turbo is engineered with a certain amount of heat dissipation in mind. Won;t you 'cook' the turbo by putting the blanket on it or cause premature wear?
I remember from my Bsc in engineering that the turbo charger exchanges potential (inertia) energy between the exhaust gas and the intake gas. Potential energy in the gas is a technical term for the speed of the gas. What happens in fact is: the turbine takes the mass of the gas, multiplied by its speed and turns it into angular momentum and speed. Then at the compressor side it happens vice versa. The thought that I'm trying to convey here is that the turbo utilises the speed of the exhaust gas, not the pressure differential. Now, the speed of the exhaust gas will be that of the speed of sound at its temperature. The speed of sound always only depends on the temperature(as long as the gas mixture stays the same and not suddenly becomes a different gas or so). Low temperature gas has a low speed of sound and the speed of sound is high in a high temperature gas. When the gas flows from a high pressure place to a low pressure place, it will travel at the speed of sound. Less than an atm. is needed to make a gas flow at the speed of sound. The reason to keep the exhaust gas hot as it "shoots at the turbine" is because then it shoots the fastest. The faster the exhaust gas bumps into the turbine the better. The speed of sound at 400C(red-hot steel) is about 575m/s while at 1200C its about 1000 m/s. I may be wrong of course. Let me know if you find out this is not why a blanket on the turbo makes it work better. Cheers.
Hey, cool video! As someone who has driven cars with NA motors, I've always wondered why some people chose to cover their turbos this way. Thanks for the explanations.
I have done my own research on this topic, and giving what I have learned, I agree with everything you said. Well done. Since you have that laser temperature measured Doohickey.. test out how effective that reflective gold film is. Clearly it does something, (i.e. McLaren F1). I'm interested to know how well it works tho.
Do turbo blankets wear out the turbo faster? Seems like a more severe environment for the CHRA. Maybe more oxidization of the metal parts of the turbo too?
Definitely make more of those videos, It is really interesting to learn and see how *go fast merch* really handles from a scientific point of view, rather than "feeling the difference". GJ
One of the more common explanations I've heard is keeping the impeller side as hot as possible, and limit that heat to the turbine housing. The rest of the exhaust will be a lot cooler and, hot fluids/gases will flow towards colder environments (kind of like the EJ20 engine having an oil reservoir above the turbo to allow cooler oil to flush through the bearing interface via thermo-capillary action). Be it the exhaust pipe (which is designed for it) or the hood (not so much). Also, if running higher swirl densities with water, ethanol, or methanol injection (or even an E85 tune) you're going to have more moles of gas getting flushed through the impeller. Controlling its radiated heat that's wasted is incredibly important, and why most turbo cars have a lot of heat shielding around them. Although that's one of the nicer looking turbo blankets I've seen. Oh, and 30% + 60% = FTW. ;-)
one point i did not hear which is the down side of turbo blankets is if you have an oil cooled turbo it traps the heat. So you really need to let the car idle or drive very easily for around a min or 2 before you shut down the car. Most cars with out turbo blankets usually just idle for 15-30secs they are good to be shut down but because of that turbo blankets ability to hold concentrated heat which excessive heat will break oil down leaving soot and other deposits in your turbo, and turbos do not like broken down oil. So you need to give it some extra time to cool down. This will help extend the life of your turbo. Make sure to also only run synthetic oil but that almost goes without saying.
Alot of the older rotary race guys around here are firmly against exhaust rap and or turbo blankets,they use that (im unsure of its name) that thermo plate stuff,very flexible and work able,around inlet runners,exhaust housing,dump pipe and extractors,you can touch it after a run and it's only warm
Thermal shielding makes a huge difference and when you have the money. To do it correctly it starts in the cylinder and goes out from there. Coating for pistons, cylinder head and valves. The exhaust ports are then coated with a ceramic thermal bearer. Now the exhaust system thermal coatings and other types of bearers can be used and it all adds up.
great video! quick question though, so turbos make heat, thats a known fact but why on the 4g63 Evolution engine do they put the turbo a heat producer next to the main source of cooling, the radiator?
I love these bro-Science videos. I work for GE on gas turbine for power generation plants. And it’s true about the blades growing with the case and closing up the clearances in side making it more efficient. On the bigger Turbines that have bucket width of 19 ft. They take in to account not only thermal growth but also centrifugal growth. Awesome video even if it was a long time ago. Lol
The claim about bringing the turbine blades closer to the housing (reducing clearance) is easily checked, without ever breaking out a clearance gauge. Find out the material of the turbine wheel, the material of the turbine housing (I'd imagine that aftermarket turbo manufacturers publish this?) and check the rates of thermal expansion for those two materials on the interwebs. If the turbine wheel material has a greater rate of thermal expansion than the turbine housing material, then increasing temperature necessarily draws them closer. That begs the question, of course - does reducing that clearance actually improve performance? Does decreasing that clearance flow overcome any negative effects (reduced exhaust density, increased deformation of the turbine wheel, increased maintenance costs due to increased creep rates, etc) to make it worth it? That's up to each car owner to decide. If turbo blankets were worth it for the OEM, they would have included it, at much lower cost than the aftermarket. It's not like thermal insulation is unknown to automotive engineering. So don't put one on your otherwise stock Focus ST or whatever.
Even if there is no performance gain, it's ludacris to not run one, especially in a tight location. They have made a world of difference on my 2 cars, so much so I can basically rest my hand one my turbo when & after its been running. p.s. Liking the vid Rob!
I did a ceramic coating and lava rock wrap on my manifold, turbo and downpipe and I witnessed about a 600rpm difference from where the car would make 1psi of boost. I did the test back to back the same day and did multiple pulls to confirm it.
you should try the gold reflective tape under your hood to see if it helps with heating up your hood. Maybe do the intercooler while your at it too. Definitely cool to watch and learn from this vid
Don't trust the temp readings that the infra-red cameras show. They need to be calibrated for every different surface as the emissivity varies from surface to surface. You can't just point and shoot. Many IR cameras allow you to change the emissivity value and you'll notice the temp reading changes as you do this. The way to calibrate it is to point it at a surface of known temperature and adjust the emissivity until the temperature reading on the camera is correct. Most accurate way is to invest in a type-k thermocouple.
Rob, Would you see any more efficiency using a blanket on a smaller turbo (like the TD-04 in my WRX), or does it not put out enough heat to make a difference with or without the blanket?
According to the laws of thermodynamics even a naturally aspirated engine could benefit from thermal insulation. If the difference in temperature between the flowing continuum (air, water, whatever) and the sidewall of the tube is lower, the friction is less. That means, if you keep your exaust heat in the pipe, and in the turbine housing, the metal parts will be closer to the EGT, thus reduceing flow friction. It is gonna put more thermal load on the turbo and the pipes, but on your level of performance Sir, it ain't gonna cause a problem.
Not to forget the fact that raising exhaust gas temperatures lead to premature turbo bearing and shaft failure and higher probability to oil coking because the turbo can't properly vent and cool off enough before shutting down but in your case since it's so close to other important components and right next to your hood, it would make total sense to buy a turbo blanket
couple of questions if there are any mechanical engineers (or genuinely knowledgeable auto mechanics) here. How does this affect cooling of the turbocharger. Both during operation and after engine shutdown? Given the is contained, would I need to run the car at very low power or idle for longer to allow the oil to cool the turbo?
i am recently searching DEI wraps and point me to this informative video, great explanation of something i never though of, feel it a interesting topic. Question... if you wrap the exhaust side of the turbo so more heat will be used to rev the turbo faster, does it also mean the intake side of the turbo got much hotter and less dense of air coming in?? guess there must be a interaction point beyond where wrapped overtake non-wrapped, and vise versa... imho, there is no such a thing absolutely better than the other, it is all depend on your driving conditions, if you are just a daily driver with a oem small turbo, and not usually rev your engine to 5000+ rpm (i am talking about cylinder engine, not rotary that 5000 rpm might be a minimum requirement for driving, jk if i am wrong), a turbo blanket may reduce power as the heat will be soaked to the intake side while you don't have high turbo rev to compensate the loss of air density, but i would wrap the intake pipe in this case to ensure a denser air supply from ambient, but if you like revving your big turbo engine frequently and drive fast alllll the way, you may want this blanket for the turbo while intake wrap makes minimal difference, as turbo occupies large portion of air intake, and the air are forced into the intake too fast to be heat soaked. JUST MY 2 CENTS
For your hood claim it is possible that is the cause however my brother owns a neon srt4 that the paint is cracked/peeling on his hood where the turbo sits. The car was never repainted so for him it wasn't the same as people driving between paint booths. Is this a bad thing for him? Is it worth a turbo blanket? I get his car is no way close to yours but would be cool to hear an opinion
Yes they work, reduce engine bay temps drastically. However, the issues people tend to have when running turbo blankets for a log period of time (talking daily driver here) is that the increased heat that is kept within the ex housing also makes its way to the chra. Heating the oil and/or water more which can lead to increased wear on bearings etc.
Wait Rob idk If you put an annotation or not because I'm on mobile but you said 30% of the energy is used efficiently by the engine but 60% is used inefficiently that nakes 90%. Was that an error on your part or is there something about that 10% that can't be used in any matter such as exhaust(not applicable to turbo setups).
How does the heat blanket affect the internal heat of the turbo? Does the blanket hold a lot of that heat in causing the internal temp to increase. Colder air is denser air so the blanket might cool the engine bay temps but does it increase intake temps? Maby an idea for the next video like this one. Cheers mate keep them coming.
Just a humble request from a subscriber... Can you please make videos of the cars you have modified and how you achieved what you have from a more scientific point of view like this video?? Please please please please!! Tired of watching fanboys modify their cars, being utterly clueless about the science behind it, and brag all day long! Need more videos like this!!
You've taught me more, then what I've learned in school
Guess Rob should do grammar lessons then?
+Nick P yes, yes he should 😂😂😂😂. But you get the point
Too true mate XD (It's worse for me cause I'm Indian)
*than
LMAO.. it's not a spelling bee DB lol.Get stuffed.
All turbo & hot pipe blankets are NOT built out of the same stuff & are NOT equal & the most expensive on the market is NOT the best. Silica quilted blankets are by far the best. The goal of boosting an engine is to increase the air density to the engine & hot side heat absorbed by the cold side is counter productive to that. Plus if you're picking up hot intake air under the hood you are also decreasing the density charge. Monitor the charge temp at the engine, the lower the better.
I Put one on my 2011 Mitsubishi Evo and I have noticed that it builds boost a lot sooner than it did before without the blanket.
wrapping your headers and or entire exhaust also helps a lot too
Yes. I have a super charged mercedes C230 Kompressor and my ambient temps went down about 20F degrees.
Rust.
+Lucio Guy no. All you do is drive the car and it will evaporate moisture bud.
Thats also a really good way to crack your headers.
+datownkidd youve got thin, shitty ass headers then.
Last time I had a hole in my rubber, my race car nearly disappeared
Very informative video Rob, I run a TB on my old v3 Impreza STi. With its top mount intercooler, it would absorb a lot of heat from the turbo nearby. With the addition of the TB, the turbo area is now much cooler but more importantly the TMIC is cold to the touch, they do work.
lmao the rubber jokes....did me a big ol chuckle...
+Rob Dahm That really was an awesome spin especially cause you can tell it was basically improv.
Jokes aside, melting things like engine mounts and cushion clamps is a VERY real concern when packaging turbos for OEM applications. Been there, done that.
IMO, I'd strongly consider a bunch of heat wrap on your down pipe, in addition to the blanket, Rob. If you run it down a ways you may get rid of some of that interior heat too.
Good job with the video. I have one thought. Your shiny intake has a very low emissivity. Meaning that it reflects infrared light. Not convinced the heat you saw in the infrared image was real. Most likely reflected IR light from the turbo housing. You will need to take temps of intake with a contact probe to confirm actual temps.
I would love more videos like these.
Quick question, with the heat trapping effects of the blanket, what does that latent heat do to the oil/water that remains in the turbo once it is shut off? Would the blanket introduce an environment that promotes oil coking?
love my turbo blanket so far. really noticed a more consistent band and earlier light spool off casual stop and go driving in my WRX
hey since you have a thermal camera how about a similar video comparing stock vs header wraps vs ceramic coatings......maybe even both combined, a lot of people remove heat shields to install headers, heat gets transferred to oil pans and transmissions
Turbo blankets are always good! someone on NASIOC took their thermal camera, and tested blankets/gold tape/and some other items and came out with some good info.
This is why I really like turbo blankets & full exhaust wraps. They protect everything from the heat, and I think they keep the heat in the exhaust system, so the whole system is more consistent, the exhaust flows out better, and doesn't slow down & create some resistance, because of the colder sections making the exhaust flow denser, like the final parts of the straight pipes, the mufflers, or the parts of the plumbing hit with cool air.
Definitely blanket turbos. I work at a petrochemical plant, all of our steam turbines and turbo expanders are blanketed. When you insulate, it keeps the process more adiabatic and closer to the ideal isentropic process.
Literary just purchased turbo blankets and exhaust wrap for the RX7 and GTR today before watching this video,. This helps explain the spider web paint cracking I have on the RX7's hood. Very informative, thanks for making this!
You still got em? Nice cars!
Great great GREAT! Video dahm!... ive just finished a turbo upgrade on my rx7 and have been in discussion about use of a turbo blanket, the one negative that ive thought of is the fact of it holding heat in could produce moisture and also may scortch the oil!?!... great vid
i did a video similar to this last year, i had a lower quality blanket not like one you had, I only at a laster thermometer and you did a much better job than I did, good stuff man.
Less heat also decreases the possibility of engine wear or mechanical failure.
To protect the paint on the hood however, I'd just pop a reflective insulation guard under the bonnet where it's meant to be (or run methanol lolz)
I will defo second some of the comments below. Get that turbo blanket, wrap your headers and use quality lubricants including coolant. Also ensuring that your custom radiator provides good enough cooling (heat dissipation) for your particular vehicle, is never a bad idea.
All this comes down to; if you want your car to perform consistently, invest some time in researching upgrades, save up the bucks and stick to only installing quality parts.
Very informative video, thank you @Rob Dahm ;)
Doesn't rising your turbo temperatures kill its bearings faster?
I'm affraid that this would kill turbos sooner just like the wraps to the exhaust manifolds do, the temps usually increase the likeness of cracks and deformation due to expansion.
I was thinking the same thing. If your wrap the turbine housing then it cannot dissipate heat to adjacent components. Sure, the compressor and intake manifolds may be cooler but you are adding a lot of heat stress to the compressor, increasing the chance of bearing failure or a crack forming in the housing. Would it make more sense to wrap the compressor housing and intake manifolds to insulate them from engine bay heat?
+Eryk Szymanski your statement isn't wrong, but if you want to use the energy that's gonna be wasted, you must wrap up the exhaust manifold and insulate the turbine, to use as much enthalpy as you can squeeze out with your turbocharger. For sure your thrust bearings need to be cooled more than before...
You know, when you talk about performance, you always have a short blanket...it's not simply to have maximum reliability, efficiency and power at the same time ;)
This was my thought as well. Turbo blankets (as has been proven a few times) have a HUGE impact on containing heat, but at the expense of the overall longevity of the turbo. Enough to be significant in my opinion.
I'd rather opt for an inside/outside ceramic paint job. I don't think that's quite as effective as a full, thick blanket, but a proper ceramic coating will help keep temperatures more tame while still dissipating properly.
+newpa1n I absolutely agree man, in fact in my next build I think I'm going for a ceramic coating 😉
So, I need to keep the blankets on to prevent rubbers from breaking, life lessons by Dahm.
I've only been watching Rob Dahm for a little over a year now. I LOVE seeing these older videos! Rob has been so detailed and thorough for years!
Love love love real world application information videos. No speculation, just hard fact.
Turbo blanket or no, this is precisely the reason I'll be going with rear mount turbos.
I'm really surprised you haven't as well. I mean, it's out of the engine bay, further time and distance for the air sheathe to cool, easy access and install, No manifold fabrication.
Hell, on my OctoRex I've even got heat shielding where the muffler used to be .
I really like these videos really interesting and informative
Can't wait to see more about the 4-Rotor. So far it looks awesome.
because of this video, i just bought a turbo blanket for my wrx. Reason i never gotten one is that theres a hole inside the hood scoop that cools the turbo but the blanket will help during hot summer days in traffic.
I am a firm believer in exhaust wraps or coatings aswell because I have had guys come in complaining of hard starts after a hard run down the road. the cause was the heat from the header or turbo evaporated the fuel in the fuel rail
Yessss plz do more videos like these whenever you have the opportunity! Being able to walk away from a video with more knowledge than I had before watching it is always a plus in my books.
Definitely do more science videos!
Performance can be gained using a blanket due to a less thermal energy transfer between the exhaust gas and the turbine housing. A cooler turbine housing absorbs more heat from the exhaust gas (decreasing pressure, temperature and ultimately mass flow) As turbine surface temperature increases , an ever smaller fraction of exhaust thermal energy can be transferred to the turbine housing. This leads to less pressure loss and better mass flow. The major drawback to turbo blankets is a BIG increase in heat transfer engine oil. On a rotary, which has very very high EGT's normally, this could easily lead to oil coking.
I need to do research on oil coking on Honda K20C engine
Dahm kept mentioning the cost of the Turbo Blanket like it was $1000. I checked out of curiosity and they are only like $50-$150. I thought they were going to be way more expensive. Definitely worth the money for the benefits you get. Excellent video BTW.
One more thing to remember is that hotter exhaust gas has a higher velocity which help in scavenging exhaust out of the turbo and exhaust quicker which also helps turbo spool. 1 more thing to remember with a rotary is that it's exhaust gas is several hundred degrees hotter than a piston engine. Because of this heat soak is worse so a turbo blanket and thermal control is even more important with a rotary. Also the RX7 engine bay is real big so there isnt as much air flow especially when you drop a larger engine than what the factory engineers meant to be in there. A 3 rotor engine will be worse than the stock 13b and a 20b will be even worse.
Would love to see a difference between a bare turbo, ceramic coated turbo and ceramic coated with a turbo blanket. I know the ceramic coating on my ducati's exhaust helped a ton keeping heat off my leg as well as keeping the radiant heat off the parts that the exhaust is near throughout the bike.
I've worked with turbos for the past year at an airplane engine shop. going to start suggesting blankets now for the racers. thanks Rob. would love more!
When heat is contained in an object that pushes hot air, that contained heat helps push it out faster, also keeping the temps around the dump pipe and rear housing the same stops unwanted expending of metals and stops regular flow. It's like driving down the road, and in one area for 1000m its 40 degrees and after that for 1000m is 10 degrees and keeps changing. I have a turbo blanket and heat shield aswell and you can notice the car comes on boost 0.90secs faster on boost and its alot more constant. Next up is Ceramic coating
Make a video on Ceramic coat headers, rear housing, dump pipes etc?
I rarely watch through to the end, but I was genuinely interested and watched this all the way through!
Love how you explain everything using real scenarios and using your own physical testing.
presumably any given turbo is engineered with a certain amount of heat dissipation in mind. Won;t you 'cook' the turbo by putting the blanket on it or cause premature wear?
Herein lies your answer: docs.google.com/file/d/0B1DKgBxqE0JEME5wQ1pIc1N5dU0/edit?pli=1
Please post more of these videos. Loved learning about this and it was very interesting
Love the scientific angle of this video. Common sense hot-rodding instead of rumor and tradition. Keep it up.
I remember from my Bsc in engineering that the turbo charger exchanges potential (inertia) energy between the exhaust gas and the intake gas.
Potential energy in the gas is a technical term for the speed of the gas. What happens in fact is: the turbine takes the mass of the gas, multiplied by its speed and turns it into angular momentum and speed. Then at the compressor side it happens vice versa.
The thought that I'm trying to convey here is that the turbo utilises the speed of the exhaust gas, not the pressure differential.
Now, the speed of the exhaust gas will be that of the speed of sound at its temperature. The speed of sound always only depends on the temperature(as long as the gas mixture stays the same and not suddenly becomes a different gas or so). Low temperature gas has a low speed of sound and the speed of sound is high in a high temperature gas. When the gas flows from a high pressure place to a low pressure place, it will travel at the speed of sound. Less than an atm. is needed to make a gas flow at the speed of sound.
The reason to keep the exhaust gas hot as it "shoots at the turbine" is because then it shoots the fastest. The faster the exhaust gas bumps into the turbine the better. The speed of sound at 400C(red-hot steel) is about 575m/s while at 1200C its about 1000 m/s.
I may be wrong of course. Let me know if you find out this is not why a blanket on the turbo makes it work better. Cheers.
I mean... this should come as no surprise. That bubbled and cracked hood is insane! Plus, the rubber pun was good :)
I like how much you giggle when talking about rubber xD
Hey, cool video! As someone who has driven cars with NA motors, I've always wondered why some people chose to cover their turbos this way. Thanks for the explanations.
Cool video, it was interesting to see the IR images.
Please Please PLEASE do more of these!
I have done my own research on this topic, and giving what I have learned, I agree with everything you said. Well done. Since you have that laser temperature measured Doohickey.. test out how effective that reflective gold film is. Clearly it does something,
(i.e. McLaren F1). I'm interested to know how well it works tho.
lol the "holes in your rubber"
looool "holes in my rubber".... rotfl
+PunchingMegaTree Because... I'm Rick James bitch ;)
+PunchingMegaTree no rubber was used apparently......looool
+teammusketeers XD
dude, rob, yes. we need more videos like this science rules.
Do turbo blankets wear out the turbo faster? Seems like a more severe environment for the CHRA. Maybe more oxidization of the metal parts of the turbo too?
Definitely make more of those videos, It is really interesting to learn and see how *go fast merch* really handles from a scientific point of view, rather than "feeling the difference".
GJ
What is you go with blankets for headers(if there are any) and using a "thicker" turbo blanket?
One of the more common explanations I've heard is keeping the impeller side as hot as possible, and limit that heat to the turbine housing. The rest of the exhaust will be a lot cooler and, hot fluids/gases will flow towards colder environments (kind of like the EJ20 engine having an oil reservoir above the turbo to allow cooler oil to flush through the bearing interface via thermo-capillary action). Be it the exhaust pipe (which is designed for it) or the hood (not so much). Also, if running higher swirl densities with water, ethanol, or methanol injection (or even an E85 tune) you're going to have more moles of gas getting flushed through the impeller. Controlling its radiated heat that's wasted is incredibly important, and why most turbo cars have a lot of heat shielding around them. Although that's one of the nicer looking turbo blankets I've seen.
Oh, and 30% + 60% = FTW. ;-)
I know it's late but this is amazing and if you do more of these, I definitely won't complain
Rob where did the custom triangular fabbed aluminum ram/NACA underhood duct intake come from?
BEST VIDEO SO FAR DO MORE STUFF LIKE THIS!!!
this is the kinda stuff I love to see on UA-cam. I love it when MCM does it, and I'd love it if you did it more
one point i did not hear which is the down side of turbo blankets is if you have an oil cooled turbo it traps the heat. So you really need to let the car idle or drive very easily for around a min or 2 before you shut down the car. Most cars with out turbo blankets usually just idle for 15-30secs they are good to be shut down but because of that turbo blankets ability to hold concentrated heat which excessive heat will break oil down leaving soot and other deposits in your turbo, and turbos do not like broken down oil. So you need to give it some extra time to cool down. This will help extend the life of your turbo. Make sure to also only run synthetic oil but that almost goes without saying.
Alot of the older rotary race guys around here are firmly against exhaust rap and or turbo blankets,they use that (im unsure of its name) that thermo plate stuff,very flexible and work able,around inlet runners,exhaust housing,dump pipe and extractors,you can touch it after a run and it's only warm
+Rob Dahm It is quite cheap too,I'll find out what it's called today.Would love to see actual temps and results
Great video and I enjoyed the use of the infrared camera.
Thermal shielding makes a huge difference and when you have the money. To do it correctly it starts in the cylinder and goes out from there. Coating for pistons, cylinder head and valves. The exhaust ports are then coated with a ceramic thermal bearer. Now the exhaust system thermal coatings and other types of bearers can be used and it all adds up.
great video! quick question though, so turbos make heat, thats a known fact but why on the 4g63 Evolution engine do they put the turbo a heat producer next to the main source of cooling, the radiator?
In what measurement were the temps from the infra red camera? Fahrenheir os Celsius(the logic one)?
yes keep doing video's like this it helps me make informed decision for when i finally build my 2jz 240sx
Absolutely make more videos like this. As you learn teaching that to others helps you understabd even more too.
This was a good thing to cover, another would be how much does wrapping your turbo manifold/header change the temp.
I love these bro-Science videos. I work for GE on gas turbine for power generation plants. And it’s true about the blades growing with the case and closing up the clearances in side making it more efficient. On the bigger Turbines that have bucket width of 19 ft. They take in to account not only thermal growth but also centrifugal growth. Awesome video even if it was a long time ago. Lol
The claim about bringing the turbine blades closer to the housing (reducing clearance) is easily checked, without ever breaking out a clearance gauge. Find out the material of the turbine wheel, the material of the turbine housing (I'd imagine that aftermarket turbo manufacturers publish this?) and check the rates of thermal expansion for those two materials on the interwebs. If the turbine wheel material has a greater rate of thermal expansion than the turbine housing material, then increasing temperature necessarily draws them closer.
That begs the question, of course - does reducing that clearance actually improve performance? Does decreasing that clearance flow overcome any negative effects (reduced exhaust density, increased deformation of the turbine wheel, increased maintenance costs due to increased creep rates, etc) to make it worth it? That's up to each car owner to decide.
If turbo blankets were worth it for the OEM, they would have included it, at much lower cost than the aftermarket. It's not like thermal insulation is unknown to automotive engineering. So don't put one on your otherwise stock Focus ST or whatever.
One of your most interesting videos, you have my vote for more like this.
Even if there is no performance gain, it's ludacris to not run one, especially in a tight location. They have made a world of difference on my 2 cars, so much so I can basically rest my hand one my turbo when & after its been running.
p.s. Liking the vid Rob!
I did a ceramic coating and lava rock wrap on my manifold, turbo and downpipe and I witnessed about a 600rpm difference from where the car would make 1psi of boost. I did the test back to back the same day and did multiple pulls to confirm it.
We definitely need more videos like this, especially with how in depth you went to describe everything. It was perfect, keep it up.
one of my favourite videos of yours recently. i love learning about things like this
Absolutely loved the video, i was suprised myself that there was such drastic diferences by just addidng the blanket! Thanks alot for the vid man.
Thanks for doing this video. I've always wondered if they worked. Now that I know, I'll be getting one immediately.
you should try the gold reflective tape under your hood to see if it helps with heating up your hood. Maybe do the intercooler while your at it too. Definitely cool to watch and learn from this vid
What a smart dude. Well put together video, wonderful explanations, thoroughly enjoyed the depth of the answers. Subscribed.
Do more of these. Thanks!
weird question but would it be possible to include the turbo in the cooling system or have a special system?
Don't trust the temp readings that the infra-red cameras show. They need to be calibrated for every different surface as the emissivity varies from surface to surface. You can't just point and shoot. Many IR cameras allow you to change the emissivity value and you'll notice the temp reading changes as you do this. The way to calibrate it is to point it at a surface of known temperature and adjust the emissivity until the temperature reading on the camera is correct. Most accurate way is to invest in a type-k thermocouple.
Rob,
Would you see any more efficiency using a blanket on a smaller turbo (like the TD-04 in my WRX), or does it not put out enough heat to make a difference with or without the blanket?
What does all that internal heat do to your oil? Wouldn't it cause it to cake up? I really wanna know that
According to the laws of thermodynamics even a naturally aspirated engine could benefit from thermal insulation. If the difference in temperature between the flowing continuum (air, water, whatever) and the sidewall of the tube is lower, the friction is less.
That means, if you keep your exaust heat in the pipe, and in the turbine housing, the metal parts will be closer to the EGT, thus reduceing flow friction.
It is gonna put more thermal load on the turbo and the pipes, but on your level of performance Sir, it ain't gonna cause a problem.
loved this video definitely need to make more
I'd be interested in more videos like this.
Not to forget the fact that raising exhaust gas temperatures lead to premature turbo bearing and shaft failure and higher probability to oil coking because the turbo can't properly vent and cool off enough before shutting down but in your case since it's so close to other important components and right next to your hood, it would make total sense to buy a turbo blanket
I love these types of topics. I would love to see more of this.
couple of questions if there are any mechanical engineers (or genuinely knowledgeable auto mechanics) here.
How does this affect cooling of the turbocharger. Both during operation and after engine shutdown? Given the is contained, would I need to run the car at very low power or idle for longer to allow the oil to cool the turbo?
...given the heat is contained...
please do more of these type of vids man loved it
Definitely not a corny video. Learning about cars is the most important aspect of hotrodding in my opinion.
to answer your question, yes. i love the videos that discuss the theory of scientific, mathematical, and mechanical aspects of modern car engineering
I do like this more scientific style of video. It's extremely useful information!
i am recently searching DEI wraps and point me to this informative video, great explanation of something i never though of, feel it a interesting topic. Question... if you wrap the exhaust side of the turbo so more heat will be used to rev the turbo faster, does it also mean the intake side of the turbo got much hotter and less dense of air coming in?? guess there must be a interaction point beyond where wrapped overtake non-wrapped, and vise versa... imho, there is no such a thing absolutely better than the other, it is all depend on your driving conditions, if you are just a daily driver with a oem small turbo, and not usually rev your engine to 5000+ rpm (i am talking about cylinder engine, not rotary that 5000 rpm might be a minimum requirement for driving, jk if i am wrong), a turbo blanket may reduce power as the heat will be soaked to the intake side while you don't have high turbo rev to compensate the loss of air density, but i would wrap the intake pipe in this case to ensure a denser air supply from ambient, but if you like revving your big turbo engine frequently and drive fast alllll the way, you may want this blanket for the turbo while intake wrap makes minimal difference, as turbo occupies large portion of air intake, and the air are forced into the intake too fast to be heat soaked. JUST MY 2 CENTS
For your hood claim it is possible that is the cause however my brother owns a neon srt4 that the paint is cracked/peeling on his hood where the turbo sits. The car was never repainted so for him it wasn't the same as people driving between paint booths. Is this a bad thing for him? Is it worth a turbo blanket? I get his car is no way close to yours but would be cool to hear an opinion
Yes they work, reduce engine bay temps drastically. However, the issues people tend to have when running turbo blankets for a log period of time (talking daily driver here) is that the increased heat that is kept within the ex housing also makes its way to the chra. Heating the oil and/or water more which can lead to increased wear on bearings etc.
would love to see more vids like this !!
This is the first video I've seen of yours and was thoroughly impressed. Concise, informative, entertaining. Subscribed!
Great video! Would like to see more of these!
Wait Rob idk If you put an annotation or not because I'm on mobile but you said 30% of the energy is used efficiently by the engine but 60% is used inefficiently that nakes 90%. Was that an error on your part or is there something about that 10% that can't be used in any matter such as exhaust(not applicable to turbo setups).
Great info Rob,cant wait for the 4 rotor
How does the heat blanket affect the internal heat of the turbo? Does the blanket hold a lot of that heat in causing the internal temp to increase. Colder air is denser air so the blanket might cool the engine bay temps but does it increase intake temps? Maby an idea for the next video like this one. Cheers mate keep them coming.
Just a humble request from a subscriber... Can you please make videos of the cars you have modified and how you achieved what you have from a more scientific point of view like this video?? Please please please please!!
Tired of watching fanboys modify their cars, being utterly clueless about the science behind it, and brag all day long!
Need more videos like this!!