Think most will say Sato's are the best.......if you can afford/find them!
I have a set of Erion slip-on's, which are middle of the range, but sound absolutely awesome! Very, very loud!
In conjunction with a PCIIIr and TurnOne airbox:
127Bhp @ the wheel with a Durbahn off-the-shelf map
130.8 @ the wheel with custom map
Not too shabby, though I reckon a full system would probably eek out another 3-5bhp, but full systems are silly money, so unless one comes along for a very good price, I think I can live without the bit extra
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