this was the one i have just tried

2.5 inch pipe small air filter



gave a more of what a toyota supra chatter sounds like if you get me not very high pitched but nice

this one is more like 3 inch pipe and a big cossie air filter again 3 inch trumpet. This was not chatter at all, more of a flutter but very loud and seamed to go on for ages



just tried this one and it was pants! not loud and no chatter at all just gay fluttering



this is the best i have found





small bend going into an old made up filter with big to small steal pipe

this gives off nice chatter so is it the curve or filter style that does it