mine are 3 1/2' w/ my home made (KINDA), mufflers ,w/ turn downs in front of the rear axle, I built the same for a hot 406 sbc in a 93 GMC, decided to have the 3" dual ran over the axle and turned out behind the rear tires lke a camaro. I could tell the diff. when I backed out of the muffler shop bay, drove it home and pulled them off,
They are still in the barn !
I use pipe max to design my exhaust layouts. It recommends 3.5"+ for my combo, but the 3.5" is big and hanges low under the car. Just wanted to clean it up. Guess i'm stuck with it. Oval tubing is way too expensive.
