Holley 4 Barrel 600 Cfm Questions……………

(((I asked a similar question but got 2 bad answers out of 3. So here goes take 2.)))

I have a 1985 Ford F-150 with a 5.0 302 in it. I want to put in a Holley 4 barrel 600 cfm carb because i want some pretty good high performance for it. Heres what im gonna get besides the carb just to clear any contradictions:

-Intake Manifold for the carb to fit.
-New headers
-New exhaust
-Anything else i might need to make it a bit better, in time.

So thats what im gonna put in it because everything in the engine right now is stock and old.

SO MY QUESTION IS: If i get the Holley 4 barrel 600 cfm carb, will it kill more gas mileage than if i were to get a 2 barrel Holley 600 cfm carb? I am a decent driver, but i do love speed.
Plus, i can tune the carburetor so that it doesnt use as much gas right? Please help me!!! Thanks to all the answerers.
damn my bad, its automatic transmission.

Answers for The Question

  1. ?69corvette?
  2. Froggie
  3. Airhead
  4. Mister Ss
  5. W_howey