I have done the turbo addition, but its in storage right now. I just replaced the catback and am gonna get it going agin once it thaws. My question is will I need to port my wastegate? My mods are intake/RB downpipe + presilencer/fujitsubo cat back. Thanks! PS pics here http://www.cardomain.com/memberpage/491227/1
YES!! The S4 turbo is a big creeper, and even the S5 will creep once the exhaust is open enough. Go as big as possible on the port job. I ported my hole several MM larger then the flapper door. There is always some bypass, but I have not noticed any negative effects. If you're worried, port huge and then replace your flapper door with a valve head from some other car (or lawnmower).
Porting Wastegate?
Posted - Feb 02 2004 : 9:28:57 PM
The S4 turbo is a big creeper, and even the S5 will creep once the exhaust is open enough. Go as big as possible on the port job. I ported my hole several MM larger then the flapper door. There is always some bypass, but I have not noticed any negative effects. If you're worried, port huge and then replace your flapper door with a valve head from some other car (or lawnmower).