Hey, Fleet 472!
Thanks for your input. Note that the '62 Chevy II with dealer-installed 327 was running 3:08s and 6:00 x 14 tires on 4 1/2 inch rims!
By the late 60's you could get Tiger Paws, T/A's, Wide Ovals, etc. like the Mopars you mention were shod with. Plus from '65-up the 327 Novas were factory engineered with heavy-duty brakes, suspension, cooling, etc. to make a total package. Low 13s, no problem!
Caddy engines are my favorite, a 500 is going in my '64 'Vette roadster!