1972 Dodge dart custom 4 dr trying to beef up.

Hooker header, offy intake, Holley 390 4bbl, Comp mechanical/hyd cam 2 1/4" dual exhaust 8 3/4 rear with 3.55 gears will get you started really good

Wayy better cam choices out there other than comp. Check with Erson or Oregon Cam Grinding. No point in going with a cam/4bbl/headers unless you raise the compression and get the head breathing better.8 3/4 is overkill look for an 8 1/4 it will be easier on the wallet and will take everything the slant can throw at it.