So I need a new exhaust manifold and I wanna get one that allows my car to breathe and also makes it sound better but not much louder and ofc more HP. I was thinking a skunk down pipe/exhaust header or a skunk alpha series header so I want to go catless bc hfc wouldn’t give as much HP, but I don’t know how to pass inspections and what I would need to do to put the cat on without having to put on an oem manifold, assuming there will be no room to cut and put on a cat. would a hfc make my car sound any bet her? I can’t just put on a straight pipe or test pipe bc my exhaust manifold is bad. Any opinions. Idk what I’m talking about tbh.