383 is about 60 pounds heaver.I am going from back in the days.If you had a A body 383 you better be on your toes trying to race one.They were some of the quickest cars in our area.My brother had a 69 dart he bought new auto with 3.91 gears and never been beat or came close to beening beat by a 340 A body E body or B body.The only cars he had trouble with was B or E bodys with 440 or hemis.I still say answer the mans question.It don't concern a 360 at all.He wants to put a 340 OR 383 in his car.Remember he is not a fan of 360 engines. Mark.
I would take a 340 over a 383 any day. Put these two motors in the same platform and the 340 will out perform the 383 as far as I am concerned. It comes down to horsepower and weight. The 383 does not make a lot more power but is a lot heavier.