[Sixties Guy]

Bob,
My system was purchased from the Buick GS Club and was specially made for them by Hedman. Of course it will fit all GM A-Bodies so it worked well on the GTO. The club newsletter was filled with positive feedback on the system so after a few months of reading about them, I ordered one and have been well pleased. As stated earlier, I have a basically stock 400 HO with 4 spd. and 3:23 gear. I can still lug down in 4th gear, don't have to downshift to pass, just kick in the secondaries and go. I am running 2.5" outlet HO manifolds and 2.5" downpipes tapered to 3" headpipes. Am also running DynoMax Ultra-Flo Welded mufflers.
I firmly believe the x-pipe and Pontiac's traditional torque output are the major factors in keeping the 3" system a viable street option.