just got back from firing up a 4.280 by 4.250 with 6.385 with solid roller cam my grind .has the 335 cnc heads it sounds very good .i would say it may not be to far from what you want? i used the comp star callies crank had the 1/4 key way cut at callies used the SRP flat tops and the competition rpm H beam rods this should take 10+ of boost EZ