My "Hurst Olds" Formula does the 1/8 in 9.0 sec at 80 mph. I improved it continuously over the last 24 years from stock 0-60 times in the 7-8 sec range to where it is now with ram air and 350 hp in the 5 sec range.......like I plan to do with my Bonne.
Yes it is an automatic 403 6.6 L, but since I modified the engine, drivetrain, chassis and suspension, it is faster than any stock 400 Pontiac. I also changed the super speedway geared 2.41 rearend to more acceptable 3.08 ratio. The only downside was dropping its topend from 160 down to 140 mph but the tire smoking increase in torque was well worth it. This engine does not like to rev beyond 5700 rpm.
In stock form, the 4 speed Pontiac 400 accelerated to 60 in 6.9 sec and finished the 1/4 in 14.9 @ 99 mph.
Now granted if you modified the Pontiac 400, it has more potential for big HP!! It has bigger main bearing journals, stronger block, etc...It'* a Pontiac