The 337 was better overall in this test, no doubt, I just wish Ron could try my modded Indy Dual plane back-to-back and then with about a 100cfm bigger Lung (like my 1000hp or your Quick-fuel) to maybe 'even the playing field' for the dual plane

Dual planes really need that larger carb cause you really have 2 motors with half the cubes and half the carb on a common crankshaft....I know that the upper plenum was making more power than the unmodded lower. My 517 felt like a completely different motor once I took the intake off to port it...especially over 4500RPM.

Thanks so much for taking the time to post all the data...this definately needs to go to the Tech Archives!!!