340 or 408?

justinp61 said
How many rpm’s would I have to turn a pump gas 340 to run 10.00 @ 135 in my 3290# Dart.

Depending how efficient you can build it 1.25 vs 1.35 vs ? Lbs-ft per cid can make a big difference.

Say 1.3 lbs-ft and say you need 625 hp (by an online calculator).

345 cid
(625 x 5252) / (1.3 x .9 x 345) = 8,132 rpm

408 cid
(625 x 5252) / (1.3 x .9 x 408) = 6,876 rpm

Around those rpms would be my guess.