I need a new exhaust system for my completely stock engine. It has factory log manifolds although I might consider R.A.R.E. replacements.

My old system had glasspacks with no crossover, 2" up front, 2" or 2.25" in rear. That sounded fine (no resonance) but didn't have good scavenging per Jim Hand's book.

1) Is a 2.5" system (with H or X crossover) oversized for the 326? Same question for R.A.R.E. long branch manifolds. I need to keep the low end with a 2 speed automatic.

2) I don't have a welder - is it reasonable to clamp the whole system as long as I use sealant? I don't want to tow the car to a muffler shop, but might get it welded later after it's drivable.