[Jack21]

Some thoughts on stainless vs ceramic/aluminum coating on exhaust systems.

Stainless doesn't rust, and polished, it looks like chrome plating. Great for bumpers, bumperettes, fastners and other corrosion resistant applications. A little pricey though.

Stainless, however, conducts heat very well, wheras the ceramic aluminum coating reflects it. In an exhaust system, a set of stainless headers, for instance, although they won't rust, will still get hot. Ceramic coated headers (inside and outside)keep the heat inside the exhaust system. I can hold my hand about an inch away from the header with the engine running and not get burned. I have some plastic pieces installed a few inches away from the headers, and have no heat damage. Stainless won't do that for you. Had I known how efficient this coating was, I wouldn't have insulated the footboxes so well.

Sidepipes and mufflers. Obviously one can't ceramic coat the inside of the muffler so isn't rust a potential problem? First off, the heat from your exhaust is still in your exhaust when it enters the collecter and sidepipe (rather than roasting everything inside your engine compartment radiating through the header). The coating reflects heat, so the inside of the mufflers stay hot. Water is less prone to condense inside the muffler and cause rust from the uncoated inside out.