i have a 2000 s4 with a chip, cat back exhaust, upgraded dv's and i was wondering what kind of air intake upgrades they make, and which is the best one to buy, also what is another good mod to increase hp that is not that expensive ?

 

I'm still pretty much a newbie myself but I think the next best bang for your buck are downpipes and intercoolers. I'm about where you are soon as the bloody fedex guy comes with my hyperboost DVs...

 

For air intake you could always do a dareintake, it wont cost you a penny and you'll get some result
you will only have to spend a couple of hours working on it. Do a little research on this site and you'll
find answers. It's an easy doityourselfer
BTW intercooler & DP wont be cheap $$$

 

so they dont make a CAI for this car ?

 

CLICK

Theres just one of the recent discussions over "DIY dairintake style"
intakes...

most ppl seem to agree that upgrade over the stock intake isnt really needed till stage 3.