I've wrapped bike headers quite a few times, and I wrapped my car headers once. I never had a problem with rust and/or water. Do you know how hot they get? Evaporation takes place very quickly on a hot ass header. Let it run for a minute or two when you park it, and any moisture that was there should be gone.
I, myself, am going to coat AND wrap my headers for my T/A when I get them.
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I drive way too fast to worry about cancer!!!
I eat Omni GLH-S's for breakfast!!!
Your fish smells like pussy!!!