Originally Posted by NOTORIOUS VR
.2L difference (2.7L in the S4)..
That said, since it's a V6 in the S4 we usually have 2.5 to 3" DP's and then depending on the turbos setup a 3, 3.5 or even 4" single from the bid section back.
Some older guys have a dual 2.5" all the way back. In your case a single 3" would probably be easier and flow more then enough for the little K03's.
That's some awesome help thanks, I was lookin at the s4's aftermarket exhaust stuff for some ideas but that's good to know