The slant six guys have had good experience with the 390 CFM Holley.
http://slantsix.org/forum/viewtopic.php?t=18931

I upgraded from a 9625 AFB to a Quadrajet on my Barracuda.
write up here: Slant Six Quadrajet


1965 Barracuda, 225 slant six
Rods & Relics - Fort Erie, ON