Don't know what they flowed when I originally bought them from
muscle motors, but at the time I was moving from ported 906's to the stage 6's (mid 90's) and they picked me up from 5.50's to 5.30's in a stock stroke 440 in a hard tail dragster. Port job II was done by a small shop in Dallas that specialized in small block chevy's, he gave me a piece of notebook paper back then that had flow numbers on it...he was claiming on the paper that he flowed them to 341...is that possible? I won't argue yea or nay, all I can say is that they went on my 499 low deck in my hard tail dragster and ran 4.80's at 140 for years, now they are sitting on my shelf, still don't require off set rockers and the rocker stands are intact...quit bracket racing so they are waiting for a good street build. Dwayne Porter is the most experienced person I have heard of on these heads and I would love to send mine to him for evaluation but just haven't done it yet.