I think that the old VHT worked well for most people, but I could never figure out why it didn't just bake on in place, because the manifold got a heck of a lot hotter than a kitchen oven. But it did seem to make all the difference.
Good luck with it. If someone finds a reliable, easy-to-use, readily available manifold and exhaust paint, I'd like to know about it.
Last time I used some, called Plastikote "Hot Paint", I baked it in the oven at about 250 deg. C. for 3 hours. When I fitted the manifold, all the paint had fallen off within a few months. It sucked.
I found a tin of etch primer rated at 220 deg. C. I'm hoping this will be enough, and will help a high temperature top coat stick to the remaining galvanising.
Best wishes,
Chris
Just for interest, I tried to melt some lead-tin solder on the central pipe of the exhaust of a small Honda engine that had been working hard for about 40 minutes. It just melted, but nothing like as easily as it melts on a soldering iron. I'm guessing that means the temperature is about 250 deg. C. Hopefully with a larger and slower engine, my 220 deg. C. paint will be okay. We'll see...
Chris
The manifold paint from eastwood works well and STAYS ON if applied as instructed to thoroughly cleaned parts. Ceramic header paint works too, if the pipe is CLEAN and you follow the instructions. Even BarBQ paint or stove enamel is good to well over 600F.
Eutectic solder (63-37) melts at 361F. (183C)
60-40 melts between 360 and 375F(183-190C), and 50-50 melts between 365 and 420F (185-215C) Leadfree melts around 482F (250C).Brazing melts above 800F, and I've had exhausts hot enough to melt brazed repairs oftener than I'd like to remember!!
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