I have a Racing Beat 3" medium presilencer shortly after the header, followed by the ISC 3" mandrel pipe and a stainless steel Ultra-Flo muffler (same one as ISC but in stainless). It's about the 5th exhaust system in the last 12 months, mostly because I tend to smash them up or things break. I am happy with this setup (3 weekends now) and make good HP.