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AznDrgn · Posted: Tue Jan 28, 2003 1:37 pm Post subject: Ceramic coating exhaust manifold

I know this topic has been brought up before but I need some clarification. I just got my BAE turbo manifold and I'm thinking about ceramic coating it along with the turbo housing to increase life span and keep temps down a bit. I've read in previous posts that it is a good idea for an NA engine but not a turbo. Is this true? and if so why? The place that I plan to use is http://www.hpcoatings.com/ anyone use them yet?
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-'87 Jeep Cherokee 4.0L 6" of lift 33" Super Swampers

-'83 Callaway 944 2.5L turbo, 300HP, 1 of 42 ever made

jpab924 · Posted: Tue Jan 28, 2003 3:47 pm Post subject:

You have to remember that lost heat = lost power. If anything you may get a quicker spool up rate.

You have to consider this:

A turbo-charged and a naturally aspirated engine will develp about the same amount of heat because what controls exhaust temps is the air fuel mixture, cam timing, and I believe spark. (I read this somwhere some time back)

Don`t forget to run a proper exhaust (with the right dia) too large of a dia. will actually make your exhaust more restrictive. Get yourself a high flow cat (for your emmisions) and a good turbo muffler (seeing that there already is a restriction in your exhaust-----the turbo charger) Having a turbo charger quiets the engines exhaust down considerably.

.... choose a muffler wisely. Get a muffler with good flow characteristics.

IMO, I would vote for getting your exhaust manifold ceramic coated (or even try jet hot?) Use a reflective color, not black. I`d leave the turbo alone.

OK...this is just my opinion and you are the one who makes the final decision......I am not responsible for any maladys that may occur!

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

that thing about ceramic coating not being good with a turbo seems wrong.

The only thing I could think of would be of you were coating the inside of the manifold. If you use a cheap coating or the prep work is not done properly the ceramic can lift and break up because of repeated expansion and contraction. Turbos probably don't like small bits of ceramic being thrown at them. The bright colours are worse for this and the "chromes" are the worst of all because of the high metal content.

If you're only doing the outside of the manifold then it doesn't matter. Theoretically the insulating properties of the ceramic should help keep heat in the manifold and reduce the heat in the engine bay basically like wrapping the exhaust which all the turbo boys say is a good thing.

As for colours, black is the purest ceramic (least amount of metal added) and will last longest.
_________________
1979 924 (Gone to a better place)
1974 Lotus 7 S4 "Big Valve" Twin-cam (waiting)
1982 924 (As featured on Wikipedia)

Learn to love your multimeter and may the search be with you

jpab924 · Posted: Wed Jan 29, 2003 8:58 am Post subject:

Ok Ok. Pick whatever color you want I`ve heard people saying not to use black?

I`ve changed my opinion in coating the turbo....a few searches on ceramic coatings took me into some turbo forums and the guys all coat their turbos.
Alot of people are writing about Jet Hot. I`ve read nothing but praise for the product. Do a quick search, it will pop up.

AznDrgn · Posted: Wed Jan 29, 2003 3:28 pm Post subject:

Thanks for the input guys, looks like I've got some more research to do and another product to look into.
_________________
-'87 Jeep Cherokee 4.0L 6" of lift 33" Super Swampers

-'83 Callaway 944 2.5L turbo, 300HP, 1 of 42 ever made