The Dual Port & “C” Series accept the Carter or Holley STD square-bore 4 bbl carb. Carb size recommended for Dual Port is from 390 CFM to 500 CFM. for “C” Series 500 CFM and larger Use Holley No. 6299 Or 8007 Carter No.9400, or Carter No. 9500 on Dual Port – Remove kick-down arm for linkage clearance. Carbs clear “C” Series manifold without modification. Offy universal linkage 560-6230 is recommended In most Installations.
These manifolds on a stock 240 or 300 C.I. engine can Increase HP output by 50 HP! Dyno tests on a Ford six with Dual Port manifold, headers, and cam produced as much as 115 HP over the stocker!