I forget who casts them..But Hughes sells an all new Magnum based casting that seems to flow pretty weel OOTB. The one I looked at had some room for improving, but the specs this shop had (not from Hughes) was 225-230cfm with 1.92 intakes. I can tell you they look real nice. I dont think they will get much past 290 ported, but who knows. Fpr the small chamber and iron look, they may be the next "big deal".