I bought a couple cans of Seymour brand Cast Blast paint. Its says it'll work up to 1200F (yeah, right!). In any case, my manifolds have been bead blasted and I want to protect them from rusting. On the back of the can the last step says to cure at 400F. I'm probably showing ignorance, but does this mean I have to somehow bake my manifolds after painting or will they be cured once I slap them on the car and run it for a while?
I've used the Seymour "cast blast" a lot - it's good stuff. But as for being heat resistant, I don't know.
I think the general concensus here is that the only permanent way to keep headers or exhaust manifolds from rusting for very long is to have then ceramic coated (Jet Hot etc).
I painted my headers exactly according to the instructions with a supposedly quality hi-temp paint, and they're showing pocks of rust after only 300 miles. [IMG]/forums/images/icons/frown.gif[/IMG]
Roadracer reported good results by first heating his headers up with a torch (although I guess an oven would do too) and then painting them with standard black hi-temp BBQ paint. Perhaps the pre-heating is the key.