Fuel System: Will Carter Four Barrel WCFB specs?

[Stuhawk]

What was the published CFM Rating for a WCFB on a 1961 Studebaker Hawk 289 from the factory ?

I have read anywhere from 375cfm to 500cfm.

Anyone know for sure.


Stuhawk

[PackardV8]

It will be interesting if any here can reference CFM from a Studebaker publication source, as I've never seen one.

Super Tuning and Modifying Carter Carburetors by Dave Emanuel does not give detailed CFM information on specific models of WCFBs.

FWIW, prior to carburetors being marketed as a retail speed part to hot rodders and racers, there was no publishing of CFM ratings for carburetors. There was no reason for OEMs to quote CFM, as you got what they chose to install. It was known among rodders that larger engines came with larger carburetors, but we never had a reference for exact CFM. We'd read the Shop Manual specifications which gave the diameters of the bores and the venturi and look in wrecking yards for those engines which came equipped with the largest.

Another FWIW, a standard calculator says no matter how large the carburetor CFM, a stock 225hp Studebaker 289" will not use more than 350 CFM of flow.

jack vines

[Stuhawk]

It will be interesting if any here can reference CFM from a Studebaker publication source, as I've never seen one.

Super Tuning and Modifying Carter Carburetors by Dave Emanuel does not give detailed CFM information on specific models of WCFBs.

FWIW, prior to carburetors being marketed as a retail speed part to hot rodders and racers, there was no publishing of CFM ratings for carburetors. There was no reason for OEMs to quote CFM, as you got what they chose to install. It was known among rodders that larger engines came with larger carburetors, but we never had a reference for exact CFM. We'd read the Shop Manual specifications which gave the diameters of the bores and the venturi and look in wrecking yards for those engines which came equipped with the largest.

jack vines

jack,
Your probably right. That makes total sense to me.
I guess the auto manufacturers didn't start posting this carburetor cfm info until the late 60s or early 70s.

[64V-K7]

The WCFB on my 55 Pres was 375CFM

[PackardV8]

The WCFB on my 55 Pres was 375CFM

The above would appear logically correct. For future reference, can you direct us to the printed source?

jack vines

[Stuhawk]

It will be interesting if any here can reference CFM from a Studebaker publication source, as I've never seen one.

Super Tuning and Modifying Carter Carburetors by Dave Emanuel does not give detailed CFM information on specific models of WCFBs.

FWIW, prior to carburetors being marketed as a retail speed part to hot rodders and racers, there was no publishing of CFM ratings for carburetors. There was no reason for OEMs to quote CFM, as you got what they chose to install. It was known among rodders that larger engines came with larger carburetors, but we never had a reference for exact CFM. We'd read the Shop Manual specifications which gave the diameters of the bores and the venturi and look in wrecking yards for those engines which came equipped with the largest.

Another FWIW, a standard calculator says no matter how large the carburetor CFM, a stock 225hp Studebaker 289" will not use more than 350 CFM of flow.

jack vines

jack,
with that being said do you think the snout on the factory air cleaner bears this out, just asking. You would think that the snout opening would equal the approximate cfm of the WCFB carburetor. The maximum air in that it could use and the snout length would help control the velocity........

[BILT4ME]

This appears to be the most comprehensive info I found.

http://www.thecarburetorshop.com/CarterFourBarrelCarburetors.htm

[PackardV8]

jack,
with that being said do you think the snout on the factory air cleaner bears this out, just asking. You would think that the snout opening would equal the approximate cfm of the WCFB carburetor. The maximum air in that it could use and the snout length would help control the velocity........

Air filter housing snout length is at least as much for intake noise control as for any other factor. Some GM high performance cars used larger openings or dual openings. Some, including Fords and the Avanti used open element air filters, but engineers admitted it was as much for the added noise, perceived by some drivers as "powerful".

The Avanti is actually more powerful and a lot quieter with a closed air filter housing fed by a cold air duct in front of the radiator support.

A bit OT, but Europe today has strict noise regulations, prohibiting loud exhausts. BMW, VW, et al, actually have hard coded noise programs which plays through the car audio at full throttle. Passengers hear it and think it is engine noise, but those outside the car don't hear a thing. Some Japanese cars use a tube from the intake tract with a flapper valve which opens into the passenger compartment at full throttle. Again, the unknowing perceive intake roar as "powerful."

jack vines

[Stuhawk]

Air filter housing snout length is at least as much for intake noise control as for any other factor. Some GM high performance cars used larger openings or dual openings. Some, including Fords and the Avanti used open element air filters, but engineers admitted it was as much for the added noise, perceived by some drivers as "powerful".

The Avanti is actually more powerful and a lot quieter with a closed air filter housing fed by a cold air duct in front of the radiator support.

A bit OT, but Europe today has strict noise regulations, prohibiting loud exhausts. BMW, VW, et al, actually have hard coded noise programs which plays through the car audio at full throttle. Passengers hear it and think it is engine noise, but those outside the car don't hear a thing. Some Japanese cars use a tube from the intake tract with a flapper valve which opens into the passenger compartment at full throttle. Again, the unknowing perceive intake roar as "powerful."

jack vines

Very interesting and informative. First time hearing that information.
Thanks

[64V-K7]

The above would appear logically correct. For future reference, can you direct us to the printed source?

jack vines

Will try and find it. It was in print, I recall

[bensherb]

Another FWIW, a standard calculator says no matter how large the carburetor CFM, a stock 225hp Studebaker 289" will not use more than 350 CFM of flow.

jack vines

If this is the case, why would Studebaker install an AFB almost twice this size on some 289's ? And why will the 289 preform better with a larger carb? Info I've read stated the AFB Studebaker used was aprox. 625 CFM.

[PackardV8]

If this is the case, why would Studebaker install an AFB almost twice this size on some 289's,

The unsubstantiated statement given to me was GM had exclusive use of the smaller AFBs. The 625 CFM was the "aftermarket" carb and could be sold to anyone.

And why will the 289 preform better with a larger carb?

Define 'perform better' and how it is quantified/measured. It might be instructive to consider the '62 289" with a 375 CFM(?) WCFB and the '63 289" with the 625 CFM AFB were both rated at 225hp @ 4500 RPMs..

jack vines

[bensherb]

The unsubstantiated statement given to me was GM had exclusive use of the smaller AFBs. The 625 CFM was the "aftermarket" carb and could be sold to anyone.

Define 'perform better' and how it is quantified/measured. It might be instructive to consider the '62 289" with a 375 CFM(?) WCFB and the '63 289" with the 625 CFM AFB were both rated at 225hp @ 4500 RPMs..

jack vines

As to the "aftermarket " carb idea. I don't think so. Carter made 505 different AFB carbs. All to fit specific applications, so the idea of a "generic" drop on version would seem unlikely at the time. One of the main differences between them was the secondary air valve which was tailored for each specific application.

The AFB Studebaker used is virtually identical to the one Pontiac used on it's 401 in 1964, save for jetting and the balance of the secondary air valve. From what I've found its aprox 625 cfm. Also in 1964, Chevy used a 650 cfm AFB on a 327; interestingly, it has the same size secondary throttle plate as the Stude/Pontiac but an 1/8" larger primary throttle plate. Chrysler used a 600 cfm version on it's 318 in 1964. it has the same primary throttle plate as the Stude/Pontiac but an 1/8" smaller secondary throttle plate. This I know from carbs I have and have rebuilt, inspected and documented.

As for "preform better". I can only go by my "seat of the pants dyno". I don't doubt peak HP being the same or at least very similar, but when I swaped an AFB for the WCFB, I felt that throttle response was vastly improved as was low end acceleration. My car was no slouch with the WCFB but it "gits like a scalded dog" now, and it accelerates much better "rolling it on" at 70 mph in high gear. Fuel economy seems to be similar, not good, but I can't tell for sure, neither my fuel gauge or odometer works correctly yet.

I picked up an all but new 625 CFM "Thermo-quad" I thought I'd try it and see how/if it differs.

[PackardV8]

As to the "aftermarket " carb idea. I don't think so. Carter made 505 different AFB carbs.

Yes, for true, there were 505 different AFB models (for attribution) http://www.thecarburetorshop.com/Car...arburetors.htm

All to fit specific applications, so the idea of a "generic" drop on version would seem unlikely at the time.

Not strictly accurate, as the 505 different numbers is through the end of Carter AFB production in 1984 and Carter had been selling aftermarket versions for many years.

As mentioned, what I was told is GM had contracted to take a given quantity of the smaller AFBs and the calibration was unique to their engines. Studebaker didn't want to pay for/contract for development of a 400 CFM model specific to the 289". As you mention, the 625 CFM Stude AFB is essentially the same as many others. Again, second-hand, I was told it was the AFB they could have quickest/cheapest without paying development costs.

Also in 1964, Chevy used a 650 cfm AFB on a 327;

Agree, from the beginning of the 327" in '62, Chevrolet used an AFB on the 300hp and 340hp models. The 250hp 327" and the 220hp 283" were given WCFBs up through '67. Makes one wonder why, since the WCFB was still in production, why Studebaker gave the 225hp the AFB, but didn't raise the horsepower rating? Perhaps, since the R-series engines needed the AFB, it might have been more cost effective to buy more of them and put them on the 225hp as well.

jack vines

[vetteson]

Carter WCFB carburetors never exceeded 1 7/16" throttle bores. From 1952 through to early 1960's throttle bores ranged from 1 5/16" to 1 7/16". Cadillac (and others) used the "largest" WCFB produced until it was replaced, both primary and secondary were 1 7/16".