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Heat coating worth the bother?


JamieP

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Hello members -I am Peter Carter of Camcoat. I hope I am not breaking any forum rules but I would like to add some technical information regarding our coatings to this thread.

Camcoating is the application of chemical polymer coatings which, when cured at temperatures up to 400 degrees C, change properties to provide thermal insulation, corrosion resistance and pleasing finishes.

Because they are liquid chemicals we can coat exhaust manifolds and pipes internally as well as externally. The internal hard, smooth, insulating finish keeps more heat in the exhaust gas which adds to the energy available at the turbocharger turbine wheel. The combination of internal and external coatings provides the reduction in under bonnet temperature which means cooler air into the engine.

We are asked what happens to the turbo if the internal coating comes off. Over 15 years of coating turbo manifolds for cars up to Indy Champ and Le Mans LMP1 and LMP2 without a turbo failure hopefully assures you that the answer is nothing. Any internal coating coming into contact with the turbine wheel would immediately atomise into dust.

The “Racespec” coating system we apply to your Supra manifold/downpipe is exactly the same as applied to the top race cars. We are also often told that the Camcoated exhaust manifold cools much quicker than if uncoated after engine shutdown. Hope this is helpful.

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Hello members -I am Peter Carter of Camcoat. I hope I am not breaking any forum rules but I would like to add some technical information regarding our coatings to this thread.

Camcoating is the application of chemical polymer coatings which, when cured at temperatures up to 400 degrees C, change properties to provide thermal insulation, corrosion resistance and pleasing finishes.

Because they are liquid chemicals we can coat exhaust manifolds and pipes internally as well as externally. The internal hard, smooth, insulating finish keeps more heat in the exhaust gas which adds to the energy available at the turbocharger turbine wheel. The combination of internal and external coatings provides the reduction in under bonnet temperature which means cooler air into the engine.

We are asked what happens to the turbo if the internal coating comes off. Over 15 years of coating turbo manifolds for cars up to Indy Champ and Le Mans LMP1 and LMP2 without a turbo failure hopefully assures you that the answer is nothing. Any internal coating coming into contact with the turbine wheel would immediately atomise into dust.

The “Racespec” coating system we apply to your Supra manifold/downpipe is exactly the same as applied to the top race cars. We are also often told that the Camcoated exhaust manifold cools much quicker than if uncoated after engine shutdown. Hope this is helpful.

 

I've been watching this thread and I'm glad someone who does this for a living has added their say.

 

Very informative :thumbs:

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It's something I have had an interest in doing one day as well so good to have an active discussion about it.

 

As Josh said, good that Peter from Camcoat joined up to give some more info on their process as well.

 

I personally have a lot of time for companies that choose to be active in the real world and based on the applications that have used their products, no one can say it's not been tested fully!! ;)

 

Will look forward to the comparison tests with JP and Dude's cars.

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Hello members -I am Peter Carter of Camcoat. I hope I am not breaking any forum rules but I would like to add some technical information regarding our coatings to this thread.

Camcoating is the application of chemical polymer coatings which, when cured at temperatures up to 400 degrees C, change properties to provide thermal insulation, corrosion resistance and pleasing finishes.

Because they are liquid chemicals we can coat exhaust manifolds and pipes internally as well as externally. The internal hard, smooth, insulating finish keeps more heat in the exhaust gas which adds to the energy available at the turbocharger turbine wheel. The combination of internal and external coatings provides the reduction in under bonnet temperature which means cooler air into the engine.

We are asked what happens to the turbo if the internal coating comes off. Over 15 years of coating turbo manifolds for cars up to Indy Champ and Le Mans LMP1 and LMP2 without a turbo failure hopefully assures you that the answer is nothing. Any internal coating coming into contact with the turbine wheel would immediately atomise into dust.

The “Racespec” coating system we apply to your Supra manifold/downpipe is exactly the same as applied to the top race cars. We are also often told that the Camcoated exhaust manifold cools much quicker than if uncoated after engine shutdown. Hope this is helpful.

 

Hi Peter,

 

as the internal coating keeps more energy & heat within the exhaust, wouldnt that be enough to keep the under bonnet temps down.

 

why would you then need to coat the external surface of the pipe.

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Hi Peter,

 

as the internal coating keeps more energy & heat within the exhaust, wouldnt that be enough to keep the under bonnet temps down.

 

why would you then need to coat the external surface of the pipe.

 

The external coating can only improve, after all the zircotec can ONLY go on the outside.............................and it looks nicer !!!!!!!

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Christ, that is a fair bit cheaper than originally thought. Would be good to get a comparison between the 2 different companys though?!

 

TBH, i dont mean any disrespect to camcoat but i only know one person that has used cam coat and i trust his opinion, he was not happy with the results and thats good enough for me to pay the extra and go with zirotec, F1 boys cant be wrong can they.

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TBH, i dont mean any disrespect to camcoat but i only know one person that has used cam coat and i trust his opinion, he was not happy with the results and that good enough for me to pay the extra and go with zirotec, F1 boys cant be wrong can they.

 

fair comment that man.

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Any coating must be internal to have effect - turbo wise

 

Not really.

You're trying to keep as much heat in the exhaust as when exhaust gas cools it also slows. By keeping the temperature hot you'll also keep the energy in.

IF the only transfer of heat was radiant heat then yes, it would have to be internal.

In a totally untreated pipe, the heat of the exhaust gas is transferred to the pipework which is then radiated to the air surrounding the pipework. With a coated pipe (even if it's just coated externally) the coating prevents the pipework radiating its heat to the air. The result is that the pipework is kept hot and so is the exhaust gas.

It's the fact that the external coating reduces the rate that the heat of the pipework is conducted to the air that effectively improves turbo performance.

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Interesting that all the F1 related stuff is brakes not exhausts etc I wish I had more time as i would have had the pistons coated by camcoat as well. Having spoken to Pete about the motorsport connection they have is what prompted me to go with them.

 

http://www.camcoat.u-net.com/

http://www.zircotec.com/page/home/1

 

We've used Zirkotec on exhausts in the past to great effect. I know Williams used them also.

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There was a multi page article on coatings in motorsport in Racecar Engineering a few months back. What is this comparison people are talking about between Dude's car and JamieP's? Underbonnet temps or engine performance? Without back to back proper engine dyno tests under totally controlled conditions on the same engine unit and ancillaries, one with the stuff uncoated and one coated, I can see zero point in performance tests. As for thermal underbonnet measurements are the engines, turbos, manifold et cetera identical?

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Not really.

You're trying to keep as much heat in the exhaust as when exhaust gas cools it also slows. By keeping the temperature hot you'll also keep the energy in.

IF the only transfer of heat was radiant heat then yes, it would have to be internal.

In a totally untreated pipe, the heat of the exhaust gas is transferred to the pipework which is then radiated to the air surrounding the pipework. With a coated pipe (even if it's just coated externally) the coating prevents the pipework radiating its heat to the air. The result is that the pipework is kept hot and so is the exhaust gas.

It's the fact that the external coating reduces the rate that the heat of the pipework is conducted to the air that effectively improves turbo performance.

 

Radiation transfer of heat is not really applicable here , it is conduction and convection , heat moves hot to cold and given enough time and conductive materials reaches equilibrium

the heat /energy source is the combustion chamber gasses , these being real hot and full of energy and a large mass of them come into contact with the manifold pipe this transfers heat easily as the pipe is metal ,given enough time the pipe reaches the equilibrium with the gas temp , but as the pipe is conductive(metal) it heats easily ,

the pipe convects heat to the surrounding air , solid to gas heat transfer, the air is not as good a conductor as the metal its rate of heat exchange is far slower - a large mass of air and small mass of hot metal

difference in temperatures also affect the rate at which heat is transferred

If the outer of the turbo manifold is coated then you reduce the rate at which heat is convected to the surrounding air and the pipe gets hotter , closer to the exhaust gas temp - the manifold gets to cherry red without any coating under high loads

 

trying reverse this by using the hot pipe to heat the exhaust gas -

the mass of exhaust gas is still quite large and it has some temperature already even at lower power and load (less differential) and the mass of the pipe is not that large ,also a short pipe (not like an exhaust for example) and heating a less conductive medium this affects the time required to transfer heat from metal pipe back to ex gas - any gain from exterior coating would only be the rise in pipe temp versus uncoated and how much would this be ?

interior coating of the pipe reduces the rate of heat from ex gas to the conductive pipe putting a barrier to the highly conductive metal -less heat transfer to the pipe must mean more heat remains in the gas stream , the pipe temp would be reduced relative to uncoated .

if then it is further externally coated then even less convected heat to the surrounding air must result

We need a vote -lol

internal ,

external

or both

or neither

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There was a multi page article on coatings in motorsport in Racecar Engineering a few months back. What is this comparison people are talking about between Dude's car and JamieP's? Underbonnet temps or engine performance? Without back to back proper engine dyno tests under totally controlled conditions on the same engine unit and ancillaries, one with the stuff uncoated and one coated, I can see zero point in performance tests. As for thermal underbonnet measurements are the engines, turbos, manifold et cetera identical?

 

Whats the et cetera Chris, I don't think Ive ordered one!!!! If JP has one then I want one:blink:

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Radiation transfer of heat is not really applicable here , it is conduction and convection , heat moves hot to cold and given enough time and conductive materials reaches equilibrium

the heat /energy source is the combustion chamber gasses , these being real hot and full of energy and a large mass of them come into contact with the manifold pipe this transfers heat easily as the pipe is metal ,given enough time the pipe reaches the equilibrium with the gas temp , but as the pipe is conductive(metal) it heats easily ,

the pipe convects heat to the surrounding air , solid to gas heat transfer, the air is not as good a conductor as the metal its rate of heat exchange is far slower - a large mass of air and small mass of hot metal

difference in temperatures also affect the rate at which heat is transferred

If the outer of the turbo manifold is coated then you reduce the rate at which heat is convected to the surrounding air and the pipe gets hotter , closer to the exhaust gas temp - the manifold gets to cherry red without any coating under high loads

 

trying reverse this by using the hot pipe to heat the exhaust gas -

the mass of exhaust gas is still quite large and it has some temperature already even at lower power and load (less differential) and the mass of the pipe is not that large ,also a short pipe (not like an exhaust for example) and heating a less conductive medium this affects the time required to transfer heat from metal pipe back to ex gas - any gain from exterior coating would only be the rise in pipe temp versus uncoated and how much would this be ?

interior coating of the pipe reduces the rate of heat from ex gas to the conductive pipe putting a barrier to the highly conductive metal -less heat transfer to the pipe must mean more heat remains in the gas stream , the pipe temp would be reduced relative to uncoated .

if then it is further externally coated then even less convected heat to the surrounding air must result

We need a vote -lol

internal ,

external

or both

or neither

 

Damn thats exactly what I was going to say but you beat me to it !!!!!!

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