I can tell you this much, from my families experience and others that I know that have done this.... putting stock good 340 heads on a 318 really... really wakes them up. !
its was in the dc booklet under 13 second 318 build section
318 headers 2 1/2 exhaust 340 j heads 213 purple shaft torker 650 dp spray 3.23s 727 shift kit
1968 dart 270 i won alot of money with that setup paid for the car and all the parts plus more
the heads added bigtime reved nicely to 6200 really needed 4.10 gears but i loved top end racing then
4 wheel drums awfull@130 mph
one of the best sounding mopars ive had
