mean buzzin you are correct, race cars also have no cats and pipe for an exhaust....all i was saying is that on the audi if you haven't gone catless then primarily that is what is holding the turbo back from spooling up, im not trying to be a dick cause you are defineltly correct in saying that if ur filter is clogged obviously theturbo will spool slower, but the cat is a pretty restrictive filter.

my emissions is up this month so im really having a hard time deciding if my cat is going to be in my car anymore...any thoughts...actually im just gonna start a new thread haha

 

X2

 

I recently purchased the AEM CAI and installed it on my 08 A4 with the 2.0T with a giac stage 1 tune. No, I didnt notice any real performance gains or anything but it at least sounds cool as hell. Im glad i did it.

 

I know this post is quite old but this answered my very specific question on the salvage B7 I am restoring which the previous owner did the exact same thing.
Thanks for saving me some money.