Quote Originally Posted by vortec king
on the flow bench i used they flowed a set of stock 062's and got 197cfm on the intake and 140?cfm on exhaust, the bench i used was a superflow 1020 and works well. I think those numbers that carcraft,chevyhiperformance,hotrod, and most cylinder head manufacturers post numbers a bit on the high side to possibly promote sales.or like what the other guy said every flow bench could be a bit different. if you go to car craft and go to the cylinder head database-under 170cc and smaller, the vortec head they listed flows 239cfm on intake, which in my opinion, is probably BS. i would like to take the head they flowed and flow it on my flow bench and see would the flow numbers really are, probably less than mine. have you guys ported a set of vortecs and flowed them?
Yes we have ported a set of Vortec's.
Most of the time out of the time from looking at my records I see with a 1.94/1.5 valve I see 215 to 220 at 28 inches of water and .500 lift.
Also keep in mind the valve design,valve job,combustion chamber work will effect these numbers also.
Yes, sometimes their numbers are a bit in-flated.
Even if you look at Scoggin Dickey parts catalog thet rate the L31 Vortec heads at 239/147, at .500 and 28" of H2O,that is a stock" out of the box "head .