390 vs 408

There is a 500 Crank HP 390 down here - runs 11.9s -

Frankly I'm having trouble working out why 18 cubes and a minor bore size difference would suddenly make a 408 soooooo much faster than a 390?

Not saying there won't be a difference, but its in the heads that the differences will show.

:rant on: - I think the real issue is, guys who build 390s come from a 318 base point - they still haven't got their heads around the need for big breathing heads!

- Maybe likewise, the 408 guys are already running bigger heads from their stock 360 days and so its less of an "issue" for them? :rantoff:

Either way - The big "must" with any stroker is the heads - you need port volume if you want to MPH.

Remember, DodgetKboy's engine is built for torque, not MPH, so don't judge potential HP on his build - as his is a stump puller! (No disrespect intended) .