340 4 barrel and 340 6 barrel: were they really UNDERrated?

My friend Bob Shapinsky of Scottsburg Indiana raced his 69 340 727 Barracuda w/4:10 gear( 3.23 stock)to a best of 12.75 @110 @ Edgewater Ohio. Ran '75 thru '78 Much modded, fenderwells...