what carb to use?

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74slnt6

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what carb cfm would anyone reccomend that i use on my 440?

engine specs -

stock stroke
.030 over bore
edelbrock performer intake manifold: idle - 5500
440 source stealth heads 2.14 intake 1.81 exhaust
1.5 valve spring ratio
.468 lift cam 268 duration i think... (440 magnum cam, whatever the specs)
about 10.75 to 1 comp.

?
 
Rule of thumb for cfm carb selection

cfm = (Engine CID X Max. RPM)/3456

This assumes 100% volumetric efficiency at wide open throttle.

To correct for volumetric efficiency use 75% for low performance, 85% for high performance and 95% for full race-prepped engines.

Hypothetical example (440 X 6000)/3456 = 764 cfm

Hi perf correction 764 X .85 = 649 cfm

Can a larger carb be used? Sure.
Will the car get lower ¼ mile times with a larger carb? If set up properly, probably.
What is the drawback to using a larger carb? In this application, a 650 would give better throttle response than the 750 (i.e. less bog).
 
You'll be sorry if you use anything smaller than a 750cfm ! that V/E formula was valid 30 years ago before modern cly heads, fast rate cams, intakes ignitions ect...
 
hey guys thanks a lot, and its a 727 tranny stock, but for a slight trans pak and a 3000 stall tc .
 
That is almost the exact same setup as I have on my 440 with the exception of the cam. I've got a Speed Demon 850 with annular boosters, mechanical secondaries and I love it. Starts good and runs really, really strong.
 
I'd go with at least a 750 carb..i've had great success with Quick fuels not so with Demons:thumbdow::thumbdow:..that cam is a little on the small side too..
 
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