From experience with many cyl hd/cams/intake combo's over the yrs, the RPM is to large for stock heads other then the RAIV/SD 455 port size with RAIV and larger size cams.
Its lazy under 2500 rpm and doesnt make much more power till about 4500/5000 rpm depending on combo.

The Performer is much lighter, but the upper runners are alttle different shape and lenght which loses some power in the upper rpm vs a stock intake.
Been over 20 yrs since used one so dont remember rpm range vs stock intake.
Probly not much.