After reviewing the specs, on your 383 combination, (good looking combo you've built for sure) one of our big throttle blade/smaller venturi HP body equipped 4150 gasoline double pumper carburetors is what we would build for your application

Here is some basic info on the carb I am talking about: This blade/venturi combination that we have continually developed over the years, offers us the best of both worlds. It offers, lots of low speed signal to give us a good high rate of engine acceleration. But by incorporating a big throttle blade equipped Billet baseplate, it gives us more high rpm power as well. You get the the best of both worlds that way with no compromises.

As you can be expect from a custom carburetor, it has our adjustable air bleed configuration, non-stick gaskets, Drag float, jet extensions, Billet baseplate, anti siphon mods for clean braking, a complete wet-flow portfolio (for easy jet selection, but we're usually dead on or within 2 jet sizes), a real sharp piece with stepped dog leg boosters, big sight glass bowls and hi-flow needle and seats.

Typically I see a 15-30 hp improvement over an off the shelf unit with much better consistency and EXCELLENT driveability.

We'll size it for the exact cfm range when it is on the wet flow bench to match your programs needs. But it'll probably end up being in the 830-840 REAL cfm range.

We don't pull off the shelf as each design is custom built to minimize or completely eliminate customer tuning requirements (we even try to set the idle dead-on for you).

Patrick James