Topic: GT500 Exhaust Manifold Finish Question

[kkupec02]

I am taking the headers off of my GT500 and putting back on the original exhaust manifolds which are in great shape. Am I better off blasting these and painting them with a high temp silver engine paint or leaving them as is with what I believe may be the original factory coating? Would the original factory coating be more durable that today's engine paints? Thanks

[kkupec02]

ps. I will of course have to plane the mating surfaces and replace the studs as well as clean up the threads.

[RoyceP]

They were bare cast iron originally. By the time the first owner had it they were starting to get rusty.

[carlite65]

I am taking the headers off of my GT500 and putting back on the original exhaust manifolds which are in great shape. Am I better off blasting these and painting them with a high temp silver engine paint or leaving them as is with what I believe may be the original factory coating? Would the original factory coating be more durable that today's engine paints? Thanks

what do you believe is the 'original factory coating'? as stated they were bare cast iron....

[Bob Gaines]

what do you believe is the 'original factory coating'? as stated they were bare cast iron....

+1 reply #2 . There was no coating originally. They were bare cast iron with no coating..

[kkupec02]

Got it. Thanks. I looked for info in our data base and couldn't find anything. Thought they may have been silver but I was wrong.

[69GT350H]

Would something like this be acceptable?

Eastwood Factory Gray Hi-Temp Coating 11.75oz aer.
Replicate the look of cast iron on manifolds, headers; protects to 1400?F

[J_Speegle]

Would something like this be acceptable?

Eastwood Factory Gray Hi-Temp Coating 11.75oz aer.
Replicate the look of cast iron on manifolds, headers; protects to 1400?F

Bought it and tried it.   
If you use that product IMHO they just look painted and the color does not reproduce the original look.

Better off IMHO, if you want to go with a paint use the darker ceramic paint that you can spray yourself or send them out. More expensive but worth it IMHO.  Remember NO gasket between the manifold and the block. Threads covering the produce (name and number) as well as ideas on how to seal the manifolds can be found in a number of prior exhaust manifold threads

[jwc66k]

Years back, we used McKay Graphite spray. A source:
https://www.aircraftspruce.com/catalog/cspages/drygraphite5200.php
It was recommended by a couple of MCA Gold Card judges, Rich C and Bruce C.
I've also used Eastwood finishes on my exhaust manifolds, but I can't remember which. I have an almost full quart can of Eastwood Stainless paint on the shelf (no recommendation - it's just on the shelf) and an unopened rattle can of Eastwood Gray 10395Z in the paint can rack.
The general philosophy is if you drive the car, the "painted by any type of manifold paint" will be altered from the exhaust's heat. After a while, some manifolds will look good, some bad. If you don't drive the car it's a different story.
Jim

[Mike_B_SVT]

Ok, what about just "curing" the cast iron exhaust manifolds in the oven like you might do to your wife's cast iron pan?

Not sure how long it would hold up at 1200 degrees or so though.

Any thoughts on that?

[J_Speegle]

Ok, what about just "curing" the cast iron exhaust manifolds in the oven like you might do to your wife's cast iron pan?

Not sure how long it would hold up at 1200 degrees or so though.

Any thoughts on that?

Not sure what product your referring to. Have used an oven to "cure" the ceramic paint part ways then later just heated them through driving. Use to cure rattle can paint after applied to bolt on parts. Seemed to help. Lower temps and only some brands would hold up to the process. Not certain with current formulas

[Bob Gaines]

I suppose it depends on the product. Many high heat paint products require the paint to be cured first for maximum protection before being put into service. Others don't. Many can be put in a oven . I have a powder coating facility close by that applies the high heat coatings and cures them in giant ovens . I have had them do headers and exhaust manifolds with great success. They use one of the more expensive professional grade products that Jeff S has mentioned before but I can't recall the name presently.

[Mike_B_SVT]

I meant like rub them down with Crisco or bacon fat and throw them in the oven to bake at 350 for an hour or so, like you would your wife's cast iron pan.  Get a nice "cured" finish so the pan won't rust.

Works great for the skillet, but the temps don't ever get up as high as exhaust manifolds, I'm sure.