I would absolutely not use 1/4" retuirn. If you use 3/8 feed use the same for the return. Absolutely would make the return at least 5/16.

I am building a 69 GTX with a 505 about 700 hp. I am running 8 AN (1/2") feed and return. Aeromotive tech support agreed with these sizes.


67 Coronet 500 9.610 @ 139.20 mph
67 Coronet 500 (street car) 14.82 @ 94 mph
69 GTX (clone) - build in progress......