welcome...from one newbie to another one...search before posting. you are going to catch flames and hell for this post man. congrats on the A4 though.
Our cars dont use "Blow-Off" Valves. We use Diverters. There is something similar to a atmospheric releasing valve (commonly referred to as a blow-off valve)called a hybrid diverter/dump valve. Our turbos need to have the air that a "blow-off" valve uses because of our maf among other things. I purchased my A4 already modded with a hybrid and didn't even know it. I have a GFB 1003 (GoFastBits.com) it sounds pretty good and it doesn't affect performace at all that i have noticed. before modding your car, do research, come up with a game plan of what you want to do any why, then go from there, just adding that valve isn't going to do much for you, if i was in your shoes, i would save, get a chip GIAC or APR, get the diverter, and start doing suspension mods etc nothing to major.
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