Hi i have just done an efi conversion on my S2. when i start to boost i can here the turbo coming in but gets to about 3000 - 3500 rpm goes flate sort of holds back so i back off the accelerater and i get a chatter from some where think its iver the damp valve or exhaust maybe both? i have tryed 2 turbos on it and it makes no change? iam thinking vacuum pipe or the pipe that goes from the housing straight to the achurater (waste gate)