I work with an old Super Stock 60's racer from "back in the day" I had a dual inline four bbl street Hemi intake that I modified & did the "Vanke" treatment to it & drove it all over the street for years with dual Edelbrock 1407 (750 CFM) Carbs. The +.060" over Hemi loved the induction set up. No back to back comparison over a stock intake though. He says it is worth 40-50 H.P. at higher RPM.