Carburetor sizing

[billdogg5]

440 bored 30 over, what size carb you guys recommend? Just a street car doing burnouts and such? Have a Holley 750 single pumper on it now. Wondering if I should upgrade

Thanks!

[DeathProofCuda]

Unless you have a bunch of money burning a hole in your pocket, a 750 Holley VS carb should be fine for street cruising and burnouts.  However, if you do want to upgrade, you'll need to provide additional details on your setup (cam, trans, rear gearing).  Those details have alot more impact on carb selection than whether or not your 440 has been bored 0.030" over.

[billdogg5]

That's pretty much the answer is was looking for haha,
But incase if I ever decide to upgrade 727 trans with shift kit, hemi grind cam 474 lift and 280 duration. Gearing right now is 3.91

[DeathProofCuda]

For your mild build with an auto trans, I think a 750 VS is probably just about perfect.  If you want to monkey around, you can probably dial in better performance with some fine tuning of jets, secondary springs, etc.

If you don't have one already, the Holley quick change vacuum secondary housing cover is a great (and cheap) upgrade for a Holley VS carb.  It makes experimenting with secondary springs really easy.  With your 3.91 rear, you can probably use a lighter spring than originally came in our Holley carb, which should wake it up a bit more.

https://www.holley.com/products/fuel_systems/carburetor_components/choke_and_vacuum_secondary_components/vacuum_secondary_parts/parts/20-59

[billdogg5]

Awsome, thanks for the info!

[Montclaire]

I've never been a fan of Holley carbs.  If you are considering Edelbrock, go 800 cfm.  I'm using one of their new AVS2 carbs and love it.  They can take a little time to get dialed in but they are fun on the street.

[Mr Lee]

I'm no expert but I agree that the one you have is probably just fine if it's set up and working right.

I've had 4 carbs on my car in the past year. Two Holleys, a Carter AVS (all were 600-650 cfm) and I also just got an Edelbrock AVS2 in 800cfm (but only because they don't make a 750).
I have a mostly stock 4 spd, 383 with a mild cam and was running a holley 650 before this but it felt lacking.  I thought the 800 would be too big but the car does pull stronger and run smoother with this carb after some jetting (down) and tuning.  Btw I like both brands of carb.

The AVS2 has annular boosters which are supposed to atomize the fuel better (looks more like a fine mist). 


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[Chryco Psycho]

I hate Eddy carbs afb or avs , they simply are not adjustable , 2x the CI is what works for me , Mopar used the 800 Thermoquad on the 340 for example .
Proform is my fav

[dodj]

I have a 30 over 440 in my car.  It used to have a holley 750vs on it. I Replaced it with a quick fuel 850dp. I like it a lot more than the holley.
But if I were doing the upgrade today,  I would go with efi.

[JS29]

I have a Quick fuel 750 mechanical secondary on my 383, I love it!    Listen to Chryco, he knows his stuff. 

[Montclaire]

I don't know, my Edelbrock seems pretty adjustable to me.  I was playing around with it earlier today, man is she smooth with the new booster design.

[Mr Lee]

I will say, one nice thing about the Holleys is all the different accelerator pump cams you have at your disposal to tune the quick shot of fuel... But I dont wanna start a carburetor war here. 


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[Chryco Psycho]

I don't know, my Edelbrock seems pretty adjustable to me.  I was playing around with it earlier today, man is she smooth with the new booster design.

Not to be mean but then you really don't understand tuning ...
The Holley designs have 11 sizes of squirters vs small , std & large , the holley has 7 pump cams with 2 positions  to tailor both the total amount of fuel & when the fuel is added vs 3 on the Eddy . there is about 8 sizes of power valve vs 4-5 springsunder the metering rods , All good carbs have removable air bleeds for both the jetting & idle circuits to tune the carb for different vacuum made using different cam profiles , this simple cannot be adjusted on any AFB or AVS type carb .
My dyno testing has shown a loss of 40+ RWHP using AFB or AVs carbs .
Having said all that EFI is far superior especially Multi Port .