Chip, that intake has been tested many times. It’s not usually the “best”, but it’s not bad. It’s about the same as an M1 4500.
We tried it on my Stage VI combo, too. IIRC, it was about the same as the modified Victor w/ a good 4150.
Above a certain point, I think the Holley's runner size is a restriction that can't be "fixed" easily because of their shape & small size (hard to access).
