Why have Header wrap and ceramic coating?

[Paulie]

If I'm wrong please excuse me...but Header wrap from what I understand is to keep the heat within the header so that your engine bay stays cool which in turn cools the air going into your intake. Ceramic coating from what I understand dissipates heat...so wouldn't that make your bay hotter? Don't these two products contradict each other?

[bgrieger]

Nope. Ceramic coatings are heat retaining, as is header wrap. Same job, different level of efficiency. The coatings are much better at retaining heat than wraps, and I would have chosen not to wrap, as ceramics that get too hot get crusty and can flake. That said, it would compliment while the ceramic lasts.

Keeping heat in the exhaust keeps engine bay temps down as a byproduct of the real benefit. Hotter gasses are higher velocity gasses. Hot exhaust clears faster than "cold" does, and helps scavenge the cylinders better increasing volumetric efficiency. The benefits to intake temps are only secondary, though they are benefits and every little bit helps.


Bob

[alltrac165]

Bob is correct about the effects of barrier coating the exhaust.
In addition to what Bob said, there are two levels of thermal barrier coating, or what is referred to as 'ceramic' coating. While the coatings do have some ceramic components, it isn't really a ceramic at all. If it were, it would crack and fall off the first time the header got hot. The levels are low temp and hi temp. The low temp is what normally goes on NA engine headers. That can flake if overheated. The hi temp stuff is normally used for turbo exhaust as it gets much hotter than normal exhausts do. I have yet to see that suffer from over heating but I haven't seen it in the cool looking colors available for the low temp, only flat black.
There are also thermal dispersant coatings that shed heat, and maybe that is what you heard about. These are not normally applied to exhaust systems, but to radiators, intercoolers, and intakes, etc.

[uluahunta]

will heat wrapping my non ceramic header cause it to crack? i heard that it can. i have the pacesetter hader.. just wondering cause the engine bay gets pretty damn hot without the stock heat shield

[uluahunta]

will heat wrapping my non ceramic header cause it to crack? i heard that it can. i have the pacesetter hader.. just wondering cause the engine bay gets pretty damn hot without the stock heat shield

[bgrieger]

Sure it can, but coating that thing may do it too. Anything that retains more heat will cause more thermal expansion in that object, and MAY cause it to crack. Pacesetter unfortunately were not all that high quality. The chance of cracking mostly comes down to the workmanship and quality of materials going into the header. Better design, weld support and material will improve the chances of staying together.

Note in every case, the answer is may or might...you won't know unless you try. Many pacesetters are still together, and conveniently, they can be welded back up if they do unlike a cast iron manifold.

Bob