Well. just thought I'd give this thread an update. Finally got a commitment from the z3, accord, optima, and GtI to go out to a farm and pull a time trial on a five mile paved loop. So here are the times for your reading pleasure
03 WRX 7:14
02 Z3 7:28
I was surprised that the Z3 didn't blow my time away, but I guess it had a harder time with the curves than I expected.