ok, i'll add my "two cents" thoughts here with a story from "the old days." when i was in my junior year in high school at john marshall in glen dale, w.va. (1971) i bought a "barely used" 68 340 formula s, 4 speed fastback barracuda from a mechanic and original owner at glen dale motors, the local plymouth dealer. "gabby" the mechanic had installed an edelbroc high-rise manifold, a holley 750 double pump, hooker "fender well" headers, and a 3:91 rear gear. with open headers and slicks, this car turned consistent mid to low 12's. i street raced a lot then and consistently beat by at least one car length 396's (non-375hp versions), Z/28's and every 383 road runner/super bee that came around. sorry to the ford guys out there but there were NO fords of any type that were even as fast as the Chevy's - let alone my "rapid transit" barracuda. one night i even beat a yenko camaro because the young steel worker who had just bought this legend incinerated the tires every time we line up. there was only one car in moundsville, w.va. that seriously threatened my cuda's race record and that was a 69 stage IV 455 4 speed GTO Judge with a 4:33 rear end owned by jim stroup. it was a beautiful dark blue car and the night we were to race, the w.va. state police showed up to ruin the show. i think i could have beat that Judge but we were never able to find out. as to a 340 vers a 383, in my opinion, the small block will always come out on top. oh, and one other thing, i currently own a 68 340 4 speed fastback formula s cuda and a 69 383 4 speed fastback formula s cuda. maybe i'll line them up some day and see which one wins.