Famous Bob I do not have any flow numbers ! As best as I remember I picked up a tenth to a tenth in half . In those days I didn’t change anything but pocket port the heads ! Probably could have got some more out of them as my tuning abilities were in the learning stages then ! I think back now and a larger carburetor and cleaning up the eddy torquer intake probably would have netted me a couple tenths or maybe even more ! I’ll never know now ! They were a neat tool tho !