Do you think my stock 2.5" intermediate pipe is restricting my engine. 305 TPI w/crane 2032 cam, 1.6 RR, siamesed base, edelbrock headers(slightly ported), high flow 3" cat., my car was running a 14.6 at 96 mph before the cam/rollerrockers.

There was definately a good improvement and I don't have a real time yet but G-tech was at best a 14.3 at an (my est.) 97/98mph. A little disappointed. I'm looking/hoping for a 14.0 or 13.9 at about 100-101+ mph.

Also a crossflow? flowmaster muffler at the end.

 

With a cam, I would say the stock pipe is hurting you a little. Get the Hooker cat-back and say hello to 14.0 , seriously though, it would definately help.

 

a 3" for a single or dual 2 1/2 should do you good
but a single 2 1/2 inch is prolly hurting you a tad