hey, I've had an 01 2.7 a6 for a while now but never did much with it since it died right after I bought it, now I got an 01 s4 and im looking to do a budget stage 3, i already have an APR stage 1 chip (not installed, may need tips there) that I picked up used for $150 but now I want to start front to back opening up the air flow so I'm looking for the best (preferably cheap) mods for the airbox and filter and hoping to find a better y pipe, I've seen some stuff about insulated ones and larger diameter ones, any suggestions out there on any pre turbo intake parts? (I'm gonna have to save a bit before buying some really big turbos). also I want to do every single thing I can to keep engine bay and intake temps at the absolute lowest, some type of diy cold air kit and heat sheilding would be great

 

The larger Y-pipe is the RS4 pipe. It's gains probably don't justify its extremely high price for what it is.