I took off my exhaust to see what was in there making so much heat. I am shocked it even runs! The cat is a (almost solid) 4" of steel material. The huge collector is just a big chunk of steel for added weight. The mufflers have 4 steel plates and 4 baffles in them. Huge restriction. This is one of the worst designs I have ever seen. Just as bad as the new 2015 diesel trucks. EPA can kiss my ass!