Last year I ran my 400SB w/ a small intake (performer 2101). Great off-idle but also very rich. Swapping to a performer RPM air gap (7501).

Will my car run:

A. Richer
B. Leaner
C. No Difference

Thanks!

Here is the setup:
Small Block 400 at 0.040" over
750 Speed Demon, Mechanical Secondary, Annular Boosters
Jets: Primary 67, Secondary 75
AFR 195 Heads
Comp Cams 286H
KB Pistons - 10.2 static CR, 7.93 dynamic CR
Scat Crank 3.75"
Headers w/ 50 Series Delta Flow and crossover
3.73 Eaton Posi

I bet it will run richer because the charge is cooled and will be more dense.

Your intake has nothing to do with how rich or lean the A/F mix is. If you're too rich or lean, tweak the carb,..start with your idle mix, then your jetting for cruise, then the power circuit.

Or perhaps the carb needs a rebuild.