Fuel System: Carburetors, 4 barrel, 259

[fatboylust]

I've searched the forum and web; read everything I found hopping to get this question pinned down; I apologize if I missed the answer. So, my current project is a 1964 Dayton HT (Canadian), which was is a 259ci, 4 barrel, with and automatic transmission. Sadly a previous owner replace the original Carter AFB #3726S with a Holley #4160, (600cfm). I have no information or reason to think there were any other engine mods as the car is still single exhaust with and the original 3.07 (Twin Traction) Dayna 27 rear end. I drove the car into the garage and have disassembled parts of the body to repair the RUST. Assuming what I've read over and over a 600cfm carburetor is not a choice of a stock 259ci engine and as a Carter AFB #3726S or equal is something a kin to unobtanium.

The question is

what are good choices for a substitute for the original Carter.
Thanks for any help.

[52-fan]

Unless you want to be absolutely stock a 500 CFM Edelbrock is the best way to go. I have one on my 259 and it is great. I have an AFB I could use, but I am going to get an Edelbrock for my pickup also.

[PackardV8]

Help us understand your question. Does the car run, drive and perform OK with the Holley? If yes, it ain't broke and don't fix it.

Assuming carbs in good condition and properly jetted, there is not a great deal of difference in how the car will feel with the Holley, the OEM Carter and the Edelbrock.

To answer the question you did ask, yes 600 CFM is more than a 259" can actually use. However, it is well to remember Studebaker Engineering chose the Carter AFB 625 CFM as the original equipment.

Most street 4-bbl carbs are vacuum secondary and won't open fully until the engine is pulling enough air to use the additional flow. Thus, even though all the 4-bbls are technically too large for a 259", they all run reasonably well.

jack vines

P.S.

a Carter AFB #3726S or equal is something a kin to unobtanium.

I think I've got a rebuilt one on the shelf somewhere. PM me if interested.

[StudeRich]

You need a 1403 or one of the other Models that have an Automatic Choke and are 500 Cfm.

Here is a 1403:

https://www.summitracing.com/parts/edl-1403

[fatboylust]

Thank you all. The information is as concise as I'd hoped for. I haven't driven it more than 100', but it started easily, idled well enough and keeping pure stock isn't an issue for me. So when the body work is done enough I'll give the current Holly a chance and if it has issues I'll get a 1403.

[Mike Van Veghten]

Fatboy -

You won't understand/feel the difference between the larger carburetor vs the smaller one unless you drive with them both, with a short span of time between the two.
Will the 600cfm Holley work, yes. Will the 500cfm Edelbrock work better, also yes.

Why...the smaller venturis of the 500's primary side will flow the fuel quicker as you step on the gas. Therefore, the quicker fuel / air delivery into the engine will help make the engine react quicker also.
"Especially"...with only having 3.07 gears. The 500cfm carburetor will make the engine much more responsive when leaving from a stop. It will also help when pushing the throttle to accelerate from a steady state speed.

Depending on how you drive, you may also see a slight gain in mileage with the smaller carburetor.

Mike

[fatboylust]

Mike, very good points, long term I'll plan on replacing the holly shortly after driving it to the alignment shop, paint shop and upostry shop...….. Your description of driving the 500cfm is what I am hoping to achieve.