Heat Wrap ?

[FDDandata]

Ive heard that heat wrap destroys downpipes/headers. If the pipes were ceramic coated or somethin would they be ok, or is there any way or kinda pipe that could stand the trapped heat?

[vex]

Ive heard that heat wrap destroys downpipes/headers. If the pipes were ceramic coated or somethin would they be ok, or is there any way or kinda pipe that could stand the trapped heat?

If they're ceramic coated, you don't need wrap.

[PercentSevenC]

The wrap might reduce the life of the pipe somewhat, but it's not going to "destroy" it, and really works wonders for reducing underhood temps. I do recommend using stainless steel or hitting it with some high-heat exhaust paint to avoid rust, though.

[FDDandata]

yeah i figured ceramic would do better to absorb heat. i think you guys answered all my questions. if theres anything else anyone thinks i need to know on the subject feel free to add

[vex]

yeah i figured ceramic would do better to absorb heat. i think you guys answered all my questions. if theres anything else anyone thinks i need to know on the subject feel free to add

Ceramic does not absorb heat.

[TitaniumTT]

Ceramic coating would be better on the outsides of intake manifolds to reject the engine bay heat. Ideally it would great to get the ceramic coating on the inside of the DP and some header wrap on the outside.

[classicauto]

a) Heat wrap won't destory a downpipe. If its a mild steel pipe, sure over 5-6years of use the wrap will hold more contaminants against it........but destory no. You should be using SS anyways since the extra cost is worth it for indestructibility.

b) Ceramic coating DOES NOT do as good a job as heat wrap 1 for 1. Comparing costs, ceramic coating gets even further behind the wrap because it costs heaps more.

c) Ceramic coating can't be transferred. You can however unwrap a downpipe/manifold and re-wrap a new one, you just lose a few bits of fiber during the process.

d) They both do their jobs, but the purpose here depends on your goal. If its exhaust you're talking about, and you want to keep the heat in there and not the engine bay - you're insulating. If you think about it as insulation - what is going to have a higher R vaule? 3-4mils of a ceramic coating, or 45mils (single layer) of wrap?

[vex]

I think a little clarification needs to be said in order to better understand:

Insulating Materials, 540*R
Blanket (Glass Fiber) Cp=--, Density=1.0 lb/ft^3, Thermal Conductivity = 0.027 btu/(h ft R)
Cork Cp=0.43, Density= 7.5 lb/ft^3, Thermal Conductivity = 0.023
Duct Liner (Glass Fiber, Coated) Cp= 0.199, Density = 2.0, Thermal Conductivity = 0.022
Polystyrene (extruded) Cp=0.289, Density = 3.34, Thermal Conductivity = 0.016
Vermiculite fill (flakes) Cp=0.199, Density = 5.0, Thermal Conductivity = 0.039

http://global.kyocera.com/fcworld/charact/heat/thermalcond.html

Strictly speaking if you do ceramic you will get more insulation with less (depending on ceramic used), however defects in application and ensuring proper curing without cracking or removal of the ceramic is something else you'll need to consider.

[SportTuner.com]

Ive heard that heat wrap destroys downpipes/headers. If the pipes were ceramic coated or somethin would they be ok, or is there any way or kinda pipe that could stand the trapped heat?

Hay Dan, I do coatings for a living and the answers above are great but I don't think they completely answer the question here.

The myth about wrapping a coated part is somewhat true and false at the same time.

Wrapping has a tendency to hold in amounts of moisture which can intensify the way the coating ages over time and speed up breakdown on poorly coated or poor quality coatings. Your coating is really only as good as the initial prep work put into it by the coater. I could say spray a million dollar coating on a part with no prep and it wouldn’t last for anything. However in the same scenario I could do an intense multi step prep process and make a poor quality coating out perform a high quality coating. Now I’m generalizing quite a bit here but at the same time I want you to understand there are good quality coatings out there that perform wonderfully. Spraying the inside of the pipe will add to the performance, however even I can’t guarantee that I can create a proper substrate inside a pipe before coating because we just don’t have tools at this point in time.

The other issue to remember here is that most coatings are not designed as a Thermal Barrier but as an appearance enhancer. All coatings will slow thermal penetration of the part which will give you a slight performance gain because it helps to hold the heat in the exhaust gasses. However there are only a few which will truly retain percentages of the heat. You must also consider the material the part is made from as well. All thermal coatings will retain heat in the part to a point which can be harmful or beneficial depending on the situation or materials used.

Another thing to consider is rotary cars exhaust gasses are generally higher than that of other cars and most coatings have a working temp zone that the rotary pushes thus increasing the speed at which the coating can fail.

And finally not all wraps are the same. Several require you to spray or paint product onto them to prolong life and maintain them and some don’t. It’s also important to remember that the wrap itself will breakdown over time too which will need to be replaced. And just like the coating the wrap will retain heat in the part for an extended period.

In general the wrap will add an additional layer of performance to any coating in this instance.

Will it increase break down or failure of the part or coating, yes to a percentage however you will most likely not notice the lowered lifespan of the part in your lifetime.

The coating and the wrap both have a lifespan and you will most likely have to redo both at some point in time depending on how hard you push your car and how well in tune you run your car.

It’s all really how you way your budget for performance. Some people will say that the amount for the percentage of performance gain is outrageous and not worth it while others will see it as a small price to pay for a gain over their competition.

Hope that makes sense of it and answers the heart of the question, if not I hope you all enjoyed my babblings…LOL

Anthony
SportTuner.com

[TitaniumTT]

Just to add to Anthony's comments above, I had Anthony and SportTuner coat ALL of my parts. Everything from the intake mani's intercooler pipes, and everything on the exhaust with the exception of the downpipe. I was more than happy with Anthony's attention to detail, timeliness, willing to work with my timeframe and everything worked flawlessly on his end.

The coating on the exhaust mani's is still intact although is has changed color slightly (although that happened quick and hasn't deteriorated anymore) and the coating on the intake mani's is still perfect. There isn't a doubt in my mind that the coatings lead to a hp increase in my setup.

Thanks again Anthony. I'll definately be sending you some more piping in the near future as I changed a few things from last year.

-Brian

[FDDandata]

thanx, yall really went in on this ? more than i expected. Im just a little lost on one answer. I still didnt read thru all the reference material but im guessing low thermal conductivity material is good, and if high or low density is good or not, or if it matters, and not sure what "cp" stands for or what the R rating is. Im guessing level of insulation.

To add to that, does thermal expansion play a factor in wrapping or coating. How im thinkin, if you wrap or coat a pipe when the pipe expands from heat i would think either the wrap would stretch a little since it wouldnt expand as much as the pipe on its own(or if coated the ceramic coating would spread & crack) and when the pipe cools the wrap wouldnt be as tight as initially wrapped. I would think something like that would happen but i guess it doesnt, unless the wrap keeps expansion in line or theres a way its compensated for. Dont know if im headin in the right direction with that but the thaught popped up

and again thanx for all your answers I appreciate the time you put into them

[SportTuner.com]

The coating on the exhaust mani's is still intact although is has changed color slightly (although that happened quick and hasn't deteriorated anymore) and the coating on the intake mani's is still perfect.

Yes that will happen. It is the pigment in the coating that doesn’t handle the heat and will fade to a degree when you heat it. This is a common and know side effect which I have yet to find a solution to solve. The ceramic media is not effected just the depth of the color. Some colors will fade less than others but will have a lower heat threshold.

Thanks again Anthony. I'll definately be sending you some more piping in the near future as I changed a few things from last year.

Well thank you for the complement and I will be happy to help you in the future.


thanx, yall really went in on this ? more than i expected. Im just a little lost on one answer. I still didnt read thru all the reference material but im guessing low thermal conductivity material is good, and if high or low density is good or not, or if it matters, and not sure what "cp" stands for or what the R rating is. Im guessing level of insulation.

The use of a High or Low thermal conductivity material really depends on what your working with and trying to accomplish both have desirable characteristics depending on the application. As far as your exhaust pipe goes you would want to use a material that is low in thermal conductivity.

“Cp” Stray Capacitance.

“R” basically put is the measurement of the insulations ability to resist the flow of heat, the higher the value the more effective it is in slowing or stopping heat flow.

To add to that, does thermal expansion play a factor in wrapping or coating. How im thinkin, if you wrap or coat a pipe when the pipe expands from heat i would think either the wrap would stretch a little since it wouldnt expand as much as the pipe on its own(or if coated the ceramic coating would spread & crack) and when the pipe cools the wrap wouldnt be as tight as initially wrapped. I would think something like that would happen but i guess it doesnt, unless the wrap keeps expansion in line or theres a way its compensated for. Dont know if im headin in the right direction with that but the thaught popped up

Yes thermal expansion does play a role, and your assumptions are correct. Yes the pipe will expand and contract to some degree depending on the material it is made of and the amount of temperature it sees from the cycling of the heat. Your wrap will also be stretched over time but not like you would imagine very small amounts and depending on how well it was wrapped will most likely not be an issue. Your wrap will probably be ready to be replaced long before it has stretched to any measurable amount. The coating will also expand and contract with the pipe. Most coatings use a binder to hold the ceramic material and pigment together and against the part. Depending on the quality of the coating it will have some ability to flex with this expansion. Over time though all coatings will eventually loose this flex and begin to fail. However this is a process that a good properly applied coating will take years to happen to.

From my experience with in the racing field most racers choose to replace wraps or rewrap parts every couple of years. Some racers will have me recoat parts at the same frequency and some will recoat much sooner for an appearance aspect due to the required frequency of appearance requirements with their contracts.

In all honesty both are well worth the expense and you will see performance gains from both.

Hope that answers your questions better.

[TitaniumTT]

Yes that will happen. It is the pigment in the coating that doesn’t handle the heat and will fade to a degree when you heat it. This is a common and know side effect which I have yet to find a solution to solve. The ceramic media is not effected just the depth of the color. Some colors will fade less than others but will have a lower heat threshold.

Yup, you even pointed that out before I sent you all the parts, that while the color may change over time and heat cycles, the thermal barrier won't.

Just incase anyone is wondering, as no-one has posted pics of Anthony's products yet, I'm sure a bunch will be posted when he gets setup as a vendor, but let me toss some up now.

Here's all the parts that Anthony coated.

http://rotarycarclub.com/rotary_forum/attachment.php?attachmentid=4775&stc=1&d=1237701211

http://rotarycarclub.com/rotary_forum/attachment.php?attachmentid=4822&stc=1&d=1237909447

http://rotarycarclub.com/rotary_forum/attachment.php?attachmentid=4853&stc=1&d=1238041854

http://rotarycarclub.com/rotary_forum/attachment.php?attachmentid=4922&stc=1&d=1238394643

You can see the difference in the powdercoating that I did and the ceramic coating that Anthony did. I'm going to try a new powder, if I can't get them to match, Anthony will be recieving everything else so it all matchs all nicey nice.

-Brian

[dudemaaan]

The mountain dew can wasn't coated wtf he missed a part! Gotta keep that stuff cold!

Back on topic, I wrapped my downpipe, and had my turbine housing ceramic coated. I think a turbo blanket works better at keeping the heat in, but it also may work too well at keeping the heat in. I use a heat shield with mine and that in itself did wonders. The wrapping is itchy if you have to work around it and have your arm on it. After changing my turbo out I had a minor rash from being leaned up against the pipe. If I was to wrap another downpipe I would seal it up with a high temp paint to help reduce the itchy stuff. Ceramic coating does look quite nice, my housing is still a nice black color.

[FDDandata]

yea i think thats it. you answered the crap out my ? and im thankful for that man. and if your work is just as good i'll definitely be sendin you some business in the future. Now is there a thread on how to properly wrap or coat a pipe.