I'd been meaning to ask the same question. 2 1/4 vs 2 1/2? Genie suggested there'd be bugger all difference in performance between the two and that the 2 1/4 would have a better note.
While I'm at it...
I'm looking at doing the exhaust and upgrading to a 2 1/2 or 2 1/4" system as I already have Pacemaker comp series headers and a hi flow cat on the thing. Problem is I don't want it too loud as the missus drives it a fair bit as well.
Anyone know of a combo that'd give a decent note without being excessively loud?
1997 EL Fairmont Ghia
XR6 Engine, Pacemakers, Hi-flow Cat, 2 1/2" Lukey sytem, XR8 intake, K & N Pod, LSD.