Sounds a lot like my old Shovelhead days...
Their problem (one of a few lol)was the domed pistons due to the combustion chamber shape, very little scavenging, the evo with oversize jugs, smaller TC style chambers, moves the air well.
and a cam in the 40 -44 range in closing intake really is fun to ride.
I have two, and take turns dreaming up new theories and try them out each winter.
Some work, some just cost money, all of them use lots of beer to apply!