Quote Originally Posted by SL65AMG
why use an A6 bottom end and a Y7 head? the Y7 is VTAAAKKK(right?) but does the bottom end have higher compression???
I had a straight A6 that was in a hatch but a little too much NOS and it overrevved and bent a valve. I had the Y7(nonvtec) head laying around so I used it. The z6, y7,y8 heads have 1mm larger valves and this setup is about 10.3:1 compression. Good throttle response and good power with less boost.