First time the headers (made by Mike The Pipe in England) where plain. Then I had them Hot Coated out in Nevada. Then I had them ceramic coated at Swantech in Scottsville. In 2017 I wrapped them with lava wrap. That made the biggest difference. I was getting over 400′ up in the engine compartment and around 250′ down the exhaust just after the bend. After wrapping the temps pretty much reversed themselves.