Best practices for keeping heat in header pipes?

[Darius Rudis]

850rwhp 427 turbo Swaintech coating at 10+ years old, all-out racecar. Yes - ugly even when new:

Previous 500rwhp supercharged Opentrack car, where I cared about looks too.
Silver-ceramic looks great, works well (just IMOHO, not as long-lasting as extreme race-duty Swaintech).

 

[Randy Folsom]

I am going to going to give this a try. If anyone has prior experience please share.

BTW, i spoke with a tech at JetHot about how they do the internal pipe coating and while he didn’t come right out and say it, he agreed the only way to apply ceramic coating on the inside is to cap off the ends and swirl it around. This at least has an applicator.

 

[JP Verweij]

Hmm not sure about rattle can stuff from Eastwood.
If its like their carb renew spray, It looks nice till you spill some fuel.

This internal coating will only stick to a new and absolutely clean surface and and like most coatings the surface has to be roughened up otherwise it won't stick.
The the only way to see if it works is to dismantle the exhaust system after a month of use to see if its still there. Ill guess that can be done with a camera.

 

[Darius Rudis]

Mine were JetHot coated, day-1 brand new. (i.e. No extra prep fees for used parts.)

 

[Joel Heinke]

I have cars with all types of exhaust coatings: 1) ~2mil thick Jet Hot, Cerakote, etc., 2) ~12 mil thick SwainTech, and 3) now welded on insulation HeaderShield.

1. My experience (and others' experience may vary) is that the thinner style coatings provide almost no heat control, even when coating applied to both sides of the pipe. It's really just there for looks and to avoid metal rusting for metals that rust. I have this type of coating on the headers and sidepipes of a Shelby style Cobra. The footboxes required additional heat shields to stop the radiant heat from penetrating. A friend got a 2nd degree burn on his leg from the sidepipe so plenty of heat was making its way through the coating as well.
   
   
2. The thicker coating provides some heat control but the majority of heat still radiates through it. So not purely just for looks but not really a heat control solution for difficult cases.
   
   I have SwainTech coated SS headers and head pipes in a Ferrari 250 GTO recreation. The exhaust system is all 304SS and runs under through the tunnel. The tunnel has 1.5 inches of ceramic oven insulation sandwiched between .050" aluminum on both sides of 1.5" chassis tubes. Until more insulation was added, I couldn't comfortably rest an elbow on the tunnel while driving the car due to radiated heat and the interior was too warm even with A/C running full. I ended up adding a layer of DEI firewall/tunnel heat shielding to top and sides of tunnel and wrapping the exhaust pipes that go through the tunnel with header wrap. After that, I can comfortably drive the car for long distances without the interior being too hot from radiant heat.
   
   
3. My homebuilt Miura represents a really difficult case. There's very little air gap between the exhaust components and critical areas (e.g. firewall, starter, motor mounts, oil pan, A/C compressor, transaxle, etc.). Given this, I decided that a "real" heat control solution beyond the spray on coatings was needed. I decided to give the Header Shield product/service a try and we'll see how well it works once I make more progress. Even using it, I applied Lizard Skin sound deadener and ceramic coating topped by DEI firewall insulation on the firewall. I also plan to use some shielding on the starter as well.

So now you have the "rest of the story".