has anyone used alcohol injection for Audis? I have recently bought a 2000 S4 6sp and am looking for bolt on upgrades. I have used alc inj on my Grand Nationals to decrease detonation and get big HP gains.Tthese have been autos so i know I will need a good waste gate to avoid overboost on manual shifts.

 

Not sure, but congrats on the new s4! [8D]

 

Alcohol or water injection will help control detonation in any motor. It can also be used in audis. The wastegate has noting to do with controlling boost on shifts. This is the job of the diverter valves(Comonly called blow-off vavles or recirculation vavles). The stock valves operate fine even for heavily moded cars. Theres also a million aftermarket valves for audis. Theres two of them. Both are under that triangular shaped engine cover at the front of the engine.