[IROC]

I'll add a few:

2.7: stock internals, European Racing Headers (George's):

Modified Supertrapps with 18 discs: 9 (glorious, best sounding exhaust I ever had)

3.2: 10.3:1 P&Cs, SSIs, SW chip:

Dansk Sport: 6 (not bad tone, but not exciting)
Triad "street" muffler: 7 (great exhaust note, but too quiet)
M&K Track "shorties": 8 (awesome sound, way too loud for anything but track use)
Dansk Sport with center outlets: 7 (nice low rumble, but doesn't sound nearly as good as a factory sport)

I'd put the Triad back on if it was louder...