XP Car's exhaust was about 10 years old and has a blown out out style second stage. Finally blowing sound at the last couple of events. Decided to do something about it. Added a 2" spacer to push the turn around to the left to get an additional 2" of canister. Old exhaust was 3" 2-stage race exhaust big brother to our ST-5. So this one is 3" in with 4" out, bigger 2nd stage. Hopefully better flow and a bit quieter!!!