Exhausts -

[Dum-Dum]

Yeah what Ruan said. The point an exhaust starts becoming a restriction on these cars is really low even though they are a 2.25" bore standard. IMO Although even a standard car will see a gain with a better system they become a real restriction at stage 1 map levels, like 5bhp maybe more. On a 150-160bhp car a hand built 2.25 with proper bends and silencers will just about be fine but thats the limit id want to run and most people if they are gonna build one will run 2.5" just to make sure. 3" is probably overkill even on the fastest HDis but for the sake of maybe £30 extra it sounds awesome. Because they rev so low on the motorway they don't tend to become droney.