y pipe = good. I'm a little confused on the rest of the details right now also. Agreement around here is that Trubendz is the best bang for your buck, and they use 2.5". I say go with that and an optimized y.

99 SVTC, T-Red, #652/2760-12.8.1998 Mother#@%@!* did I sound abstract? I hope it sounded more confusin than that!