For a racing class that requires pre 74 American production iron block and heads, with a 370 cubic inch limit, naturally aspirated, where maximum power is everything, how do you think a 4.25 x 3.25, high rpm Hemi would work out? I already have a set of iron heads that will flow 420i 315e. The Wallace calculator says these heads at this cid will make 900+ horse at 10,000 - 11,000 rpm. How high can this size hemi reliably rev, assuming all the best stuff?
What has been done like this already?
How would you build it?
Thanks, Joel
Late 70’s technology :
.030” over standard Hemi block, 6.96” NASCAR rod (can you say heavy?), standard 3.48” Direct Connection crank, DC race piston @ 12.5 to 1 (can you say heavy?) with Dykes rings, stock street Hemi heads port matched and bowls cleaned up, .750 roller, Rat Roaster manifold, auto trans, 10.5 x 30 tire. A/SM. Ran 10.30’s at 133+. Never could hook it up, but it ran out the back door like a freight train turning it 8500. Never broke anything and it was raced a lot.
This same package we went to a tunnel ram with 2 dominators, ported the heads - I think they flowed 350-370 back then, at 3400 #’s in B/MP went 9.70’s.
Current technology, light Diamond pistons, light rods, better valve gear, better intake, scrapper, who knows what that is worth.
