get the bigest mufflers u can...flow 40s r good...bombs have resp and will make you nuts after 10/20 minuits...i think my sis BF had them [he was nuts] for that car you need headers...X pipe and 2 1/4 min pipes....what engine 350 use 2 or 2 1/4.....400 CID 2 1/4 to 2 1/2 even 2 5/8