John,
The weight different between the A-Body Barracuda and B-Body Road Runner
of {+ 314 lbs.} did make a significant difference down the Track.
The #3110 lb. 340 Barracuda was much quicker off-the-line, than the #3424 lb.
383 Road Runner 'Pillared-Coupe'.
Once the Road Runner started to breathe (mid-track) it would come on strong.
I would say, that if the 68' 383 Road Runner came through with a Holley 735 CFM
(same Holley as the Ford 428 Cobra-Jets) or a 780 CFM Holley {vacuum secondary}
and an Edelbrock Aluminum Dual-Plane High Rise Intake it probably would catch
the 340 Barracuda at the 'traps'.
The Intake and Carburetor would have been worth an easy 3/10's.
