No answers for you?
wow.
I didn’t want to comment ‘cause I’m not up-to-date on these things.
I put a set of CYCLONE headers on my ‘75 in 1983.
A buddy won them at a Corvette Convention Weekend raffle.
I bought them off him immediately that night for $50.!!
They have been removed and repainted(VHT) a few times since then and still working fine.
120,000 miles..! Honest!
They are nothing special, not coated, porcelyn, wrapped or anything special.
good luck.
graham