Exhaust manifold temperature

[Nick M]

How hot does the stock cast manifold actually get? I had an idea of using my high heat engine paint with ceramic on the manifold as long as the manifold is off the car. They claim 500 degrees, and 1200 intermittently. Since exaust temps can hit 1200no problem, where does that leave the manifold?

 

[hiimjohnespino]

Not sure the temp on the exhaust manifold but they have header paint thats rated at 1200 at your local auto zone. I've used 500 degrees on my car and it became discolored so I would go with the 1200.

 

[IJ.]

I've had my header hot enough to melt the Ceramic coating I used to use Nick.

 

[Ma70.Ent]

Well if it means anything to you, jdub recommends using 2000 deg coating and he says that 1300 won't last, or something along those lines.

 

[bigboost7m]

Hmmmmm, Id go with a tubular manifold, the stainless steel looks bad ass when it gets hot, and you dont have to worry about paint coming off.......lol, jk. I think it all depends on how much you want to spend. Id go with ceramic coating if you can afford it, a good place that does coatings is:

Dart Machinery
353 Oliver Street
Troy, MI 48084
(248)362-1188

If you just want to spray bomb it, VHT makes a high heat paint rated to 2000F that I have use before, but only on the block. But it lasted for 2 years, and still looked great when I pulled the motor.

 

[Rennat]

VHT Flame Proof. good to 2000 degrees.

we used it on my friends manifold, turbo, and o2 housing (elbow) and its still on after 6months... and he BEATS on his car boosting it all the time.

 

[Nick M]

Thanks. The only VHT I know of is a substance put on the track that slicks grab a hold of on launch. I will look it up.

 

[IwantMKIII]

VHT Flame Proof. good to 2000 degrees.

we used it on my friends manifold, turbo, and o2 housing (elbow) and its still on after 6months... and he BEATS on his car boosting it all the time.

VHT is 1500 degrees not 2000, maybe intermittenly. I just ordered some last week. won't get here for another week cause they sold out of the clear coat :aigo:

 

[jdub]

VHT Flame Proof. good to 2000 degrees.

we used it on my friends manifold, turbo, and o2 housing (elbow) and its still on after 6 months... and he BEATS on his car boosting it all the time.

Question of the day...do you want it to look good or actually provide a benefit. Like cutting radiated heat to the engine bay.

Well if it means anything to you, jdub recommends using 2000 deg coating and he says that 1300 won't last, or something along those lines.

That sir, is a true statement

VHT is 1500 degrees not 2000, maybe intermittently. I just ordered some last week. won't get here for another week cause they sold out of the clear coat :aigo:

Also true concerning VHT...there's a very good reason to spec a 2000 deg coating beside problems with adhesion for the 1500 deg coatings. The whole idea is to contain the heat in the exhaust stream...hot exhaust gas maintains velocity, assisting in the efficiency of the system. If you exceed the coating's rating, the thermal barrier is compromised and heat is radiated from the manifold.

 

[Rennat]

if you cure it, its just as good as ceramic coat, especially when you buy 2 cans to do the turbo, manifold, and heat shields. i think i used an entire can on the hotside of the turbo.

this stuff and a "real" ceramic coat job are just the same, apply, and bake. whats the difference?

 

[jdub]

There's a huge difference...ceramic is cured at 500 deg for starters. The carrier matrix bonds with the metal it's applied to...even using a bead blaster it is difficult to remove once cured. In addition, metal's are part of the formula...the ceramic I use is a mil spec product originally used to coat jet turbine casings. It uses titanium as part of the ceramic matrix.

Ceramic requires specialized equipment to properly apply and cure. To say a "paint" is anywhere close as good illustrates a basic ignorance of the product and the process. The is no way VHT provides the same thermal barrier a ceramic does

Just in case you don't know...I have been coating with various ceramics for years.

 

[Rennat]

i just know that i got some stuff done, and they had a new guy working there and because the pieces were cast, he didnt bake em long enough, and the inside flaked...

and the main reason i sprayed mine was because i HATE that rusty poop red/brown color of the exhaust manifold and turbo.

 

[jdub]

You have to have a competent tech applying ceramic...the metal has to be absolutely clean. ANY oil, grease, etc will cause it not to bond. The curing temp/time is also very important. I have yet to have a part returned due to the coating losing adhesion or it's thermal properties. Sorry that happened to you, but that does not make VHT "better" or "as good" by any stretch of the imagination. I hope you got your money back.

Like I said...do you want the coating to do something worthwhile or do you want looks

 

[Rennat]

but i talked to the guy, and they used a ceramic "primer" so to speak... it was a base coat, that they etch afterwards or something, and THEN the spray the black ceramic coat on top of that, so they said its still ceramic coated, just not with color... i didnt care in the end as it was still coated.

my last engine i got a TON of stuff powder coated and ceramic coated FOR FREE! haha. not this motor though... wasnt as lucky.

i just like VHT because it holds up, is easy to apply, and i know its going to last. Im going to measure my manifold and turbo temps though and see if i can get somebody else to post up there temps to see if its really working.

 

[jdub]

I don't know what he was using, but the ceramics I have experience with do not require a "primer". In fact, that would interfere with the bond to the metal surface.

BTW - you never want to ceramic coat the exterior of a head or an engine block. The heat retention would be a very bad thing

 

[Rennat]

thats what i thought... but the place has been in business for like 30 years, and they do this one shops drag car, so i didnt really question it...

it was on my friends car anyways.

just wondering though... how much would you want for..

Turbo cold side and hot side
exhaust manifold
heat shields

maybe the lower and upper intake manifold?

 

[IwantMKIII]

VHT, does not require a primer. however in regaurds to your previous statement about curing Jdub, VHT reccomends a series of heat treatments ranging from 200*F to 1000*F. It increases its resistance to other chemicals. W/o the curing process, supposedly its resistance is minimal. I know why this is, i just am not sure the specs on it or its actual tolerances vs. a real ceramic coating.

 

[IJ.]

VHT, does not require a primer. however in regaurds to your previous statement about curing IJ, VHT reccomends a series of heat treatments ranging from 200*F to 1000*F. It increases its resistance to other chemicals. W/o the curing process, supposedly its resistance is minimal. I know why this is, i just am not sure the specs on it or its actual tolerances vs. a real ceramic coating.

I didn't "state" anything

 

[Rennat]

LOL. and go read the back of the can..


its in 200, 300, and 400 degree temps. where the hell are you going to get an oven thats going to heat an object to 1000 degrees?

OR

you can heat cycle the engine... run for 30mines, let cool down, run for 30mins let cool down, and then run it again i believe.

 

[IwantMKIII]

I didn't "state" anything

LOL, corrected. I get you two mixed up sometimes at a quick glance from the J's and the red names