Mopar Action On-line – Tech Questions
Jeff Schliep, Duluth MN , 1967 Plymouth Fury 318 2 barrel
I have a 1967 Plymouth Fury with a 318 2 Barrel that I am using for EnduroRacing. I am looking to get a little more out of her and have been toldthat by adding a 360 manifold w/2bl carb it would help more so than adding a318 manifold with a 4 barrel. Therefore what I am wondering is if the 2BBlmanifold of off a 318 is actually different than a 2BBl manifold off of a360. If they are the same then I would just have to swap carbs, if not Iwould have to swap carbs and manifold.
Thanks for your help, Jeff
Yes, the 360 manifold has bigger ports, also a bigger carb mounting pad. Aworthwhile swap, wild guess: +10 HP. if you port-match the heads (if this islegal in your class), opening up the heads to match the new manifold, youmight increase this to 15 HP or more. But best of all would be the 4-Bbl.All factory 4-Bbl SB intakes had the larger 360 ports. Keep in mind, though,for what it sounds like you are doing with the car, mid-range torque, offthe corners, is the key to winning. The upshot: Keep the 4-Bbl on the smallside (600-650 CFM.)