Carburetor CFM Selection

[CafnutS]

What would be the best CFM Carburetor for the below setup? I have a 70 Bee with a 383 CID.

https://www.jegs.com/i/Edelbrock/350/2086/10002/-1

 

[69 Sleeper Bee]

Here are the carbs they recommend to go with that intake
https://www.jegs.com/i/JEGS+Performance+Products/350/7186/10002/-1

 

[Bee1971]

Edelbrock AVS 2 - 800

If your going in the direction of Holley , they will chime in

 

[SlinktRR]

brawler 750 (holley 4150). these are great carburetors but a little thirsty.

 

[WileE]

Holley 3310

 

[rumblefish360]

800 AVS-II or a 4150 - 750/800 Holley. The Brawler is an excellent choice for a Holley.

 

[66Satellite47]

I'm a Holley guy, for the most part. The 3310 Holley was a great street carb for me back in the day. The 3310-1 was a 4150 style with screw in jet secondary metering block. Very tunable and excellent for a real wide variety of combinations. Not sure if the current 4160 3310's are as tunable.

 

[Skatpak]

Like anything there is mathematic equations that can be used to exactly calculate what your motor needs. This is a base formula that gets you in the game. It is CUBIC INCHES X RPM X VOLUMETRIC EFFICENCY DIVIDE BY 3456. Now for volumetric efficiency, for a stock motor use 80 as the starting point. as you modify your motor that number changes. What you will find is that in most cases you can run a carb with a smaller cfm than you might think and get more power. Remember dumping more fuel does not necessarily equate to more power. What you're trying to do is maximize the fuel into what the motor can get out. Play around with this and I think you will be surprised. Good luck.

 

[67charger383]

750 dp

 

[Skatpak]

Learn About Volumetric Efficiency and How it Affects Engine Performance (onallcylinders.com) This article describes it better than I can.

 

[4speed68rt]

A good working smaller cfm is better, in my opinion. More responsive and more efficient. Better for a good burnout! Its not like we are racing and need to maximize top end, high rpm power, just looking for a good driving experience. I run a 650 BG Street demon. Vacuum secondary.

 

[old guys rule]

What would be the best CFM Carburetor for the below setup? I have a 70 Bee with a 383 CID.

https://www.jegs.com/i/Edelbrock/350/2086/10002/-1

For the street, a Holley 650 CFM spread bore.

 

[cr8crshr]

750 cfm is about max for that intake...which I have on my 383ci 66 Ply Sat as anything bigger is just a waste. I put one of these on it after a Holly DP and a Carterbrock 750 as both were the dickens to get dialed in. The Demon bolts right on and a little tweaking of the air fuel mixture and it purrs like a kitten and responds very nicely/ That would be my suggestion here...cr8crshr/Bill

https://www.holley.com/products/fuel_systems/carburetors/street/parts/1904

 

[Mike67]

Summit has a calculator based on Street & Race volumetric efficiency, I was looking at them last night.
Thinking of scrapping the efi....
Has anyone used FST carbs? Seem like a lot of carb for the money?
https://www.fstcarb.com/

 

[Cranky]

The best carb I ever had on a street car was a TQ.....but they do have a learning curve for adjusting the secondary air door.

 

[Budnicks]

I'm personally not a fan of the Weber/Edlebrock carbs
(knock off of the old Carters)
Some people sware by them I'm not one of them people
they have too many issues out of the box, for the price

if you can find an old "real" Carter AFB, Competition Series 750cfm
(has a black label around the airhorn)
that is a great carb on a relatively stock 383 too

I prefer the Holley's over them

or

the Street Demon (owned by Holley) were tested on Engine Masters IIRC
in a cheap carb comparison, they did very well,
they also have a 750cfm version
(IIRC they have from 625cfm to 800cfm)

or

almost any Holley square bore 4150 etc.
the Holley 770 Street Avenger Vac. Sec. & Electric Choke
(had one on my stock 68 RR 383, way better than the Edelbrock
especially down low)
works well also, depending on what's been done to your engine
you can get them in 670cfm to 870 cfm IIRC

or

a Holley Spreadbore, if you have the right manifold
or room for an adapter for a spread-bore
small primaries & larger secondaries,
can get a lil' better milage
& still have the performance of a Holley Carb
they have various different models styles & CFM

 

[70bigblockdodge]

TQ.