best size carb on a 440? (2025)

looking at getting a different carb for my 440. should i go with a 750 or will a 600 work? thanks, 64

definetly 750, 600 will starve it i am sure

A 440 will run well with a 600 all the way through to TWO 1250 carburetors. It's impossible to recommend a carburetor for you without some specifics of your engine.

stock bottom end, stock 906 heads, edelbrock performer manifold, elec. ign. w/orange module, 292 - 509 cam kit, 727, 355 sure grip. i have ran this combo before but with an old style torker intake, mallory dual point and a holley 750 cfm dp. i was younger and had the pedal to the floor more than anything else. the 440 is a fresh rebuild that i want to drop in soon. the current 440 is pretty much stock maybe an "RV" cam at best. it currently has a holley 750 vaccum secondary carb that has seen better days. i don't plan on doing any racing just get on it some times. so i was going to get an edelbrock carb and was trying to figure out if a 600 cfm (1405) would work over the 750 cfm (1407). i would like to run it on the current stock 440 then swap it and the manifold over to the warmed over 440. thanks, 64

I think you would be better off getting the 750 vacuum secondary carburetor rebuilt. It will work fine on your current engine and the engine you plan on going with later. No need to buy another one.

Similar build, about 500 at the crank. Mine likes the 850 Demon.

This is written by my go to guy Damon Kuhn of Diamondback racing engines. Pretty good carb guy.4) Get the proper carb for your vehicle- undersized carbs, while great for response will be dead at the top end, run richer as a rule (excess velocity causes main circuits to come in wrong) and usually get worse mileage. Oversize carbs (especially vacuum / air secondary type) will have an untunable low end bog, lazy acceleration and nearly impossible idle problems. Somewhere in between is what we are looking for. A simple equation to get you close : ((Max rpm X CID) / 3456 )X V1. V1 is a variable representing the efficiency of your engine . Use .85 for a normal street engine, 1.00 for a fairly stout street engine ( we're talking close to strip car here) 1.2 for a highly modified strip only vehicle. (Yes< I know these are not the same numbers as some books show, but they work for these carbs) BE HONEST (you don't have to tell anybody) -along those lines do not use 7600 for the rpm on your hydraulic cam 8.5:1 street engine.
EXAMPLE: 440, hydraulic street , 5800 max rpm. ((5800 X 440)/3456) X .85 or ((2552000)/ 3456) X .85 or 738 X .85=627 or a 625 440, 620 lift mechanical, 6800 rpm max ((6800X440)/3456) X 1.00 or ((2992000)/3456) X1.00 or 865 X 1.00=865 or 800 (biggest) or 2 X 500
SEE how much difference it makes?
Typically, you can get away with 1 size bigger / smaller eg a 750 will probably be fine on you stock 440 …but you say " CG said his likes a dominator"….does that mean it truly works in an optimum manner?? If you have a high stall converter, 4 speed , don't care about mileage/ drivability…. by all means put the biggest thing you can find on it….

Damn dude, I've always called myself a pretty decent carb guy, but you even lost ME with all that. lol

I'm running a 750 CFM Edelbrock on a 440 that is very similar to yours and it seems to be the right size for it. I agree that a 600 CFM would probably be good at lower street rpms but your engine will run out of air at about 5000 rpm.

440 stops pulling at about 4850 per the chassis dyno. With the 850 Demon it walks off idle and could not be better on the street. Once the timing advance and adjustments got figured out it was fine. Low end grunt and snort never bogs. Ever. I've ridden in somewhat famous 440 Mopar builds that have the big block launch balk. Some think it's normal. It's not.

Ran 1500 cfm on a radical 440 (kinda radical for 1984) and it did pretty good.

Thermoquad.

The TQ is a great carb for a street car but you need to learn how to work on them. They are not hard at all one you know the particulars....

750 CFM for a mild street build with a small cam is plenty. I ran a 750 Eddy with a 272 deg cam and it's quite happy. Very crisp and seems to pull well to about 5500 RPM. Right now I have a 6 BBL and it's not as happy.

Holy thread resurrection Batman.

Well, to be fair, we're still waiting for the O.P. to chime in with his decision after getting opinions.