I'm about to order my carb. I'm thinking of getting the Jet Stage 2 Q-jet. Just wanted to know whether to order the 750 or 795 CFM version? Engine is a freshly rebuilt 350 RV Cam Flat top pistons Vortec heads Performer manifold Exhaust will (most likely) be dual 2.5", Headers, and flowmasters... Will 45 cfm's make a difference? Also maybe someone can answer this for me... Why do Q-Jets run so much bigger on cfm's for the same engine as Holleys?