I think my auto would slay a 3.73 5.0 from an 80-115 pull.
That's a bold claim. My '12 Brembo/3.73 300A is stock and I ran off and hid from the few A6s that have tried. Most of them had similar mods to you (tune and axlebacks). I've never started a race at 80mph though.
2012 P8C, HP, 300A, 55D, 457