The Stovebolt Site Forums The Shop Area Engine Shop Carter YF Question

Hello, all. I'm Tim and I was fairly active on this board about seven years ago. Then I got married and priorities changed...

Anyway I'm getting back to work on my 51 and have a question about my Carter YF's. I've picked up an Offenhauser dual pot intake and have 2 YF's for it. My only concern is I have a manual choke carb with the number 966S, and an auto choke carb with the number 2101S. I've heard that the carbs must match, but...both of these carbs are "replacement" carbs for 32-62 Chevy 6's and both are SAE size 3 carbs. Will they play nice together, or do I need to try to find another to have a perfectly matched pair?

TIA for the help! Hopefully I will be able to return the favor soon.

If the bore & venturi size are the same, Pull the tops off & make sure the hetering rods & jet are the same. If so they should work together.

My list of YF carbs show that the 966S is also an auto choke carb for the 235 engine. List is from the carb king.

Could this be a "Mix and match" rebuilt carb?

Kurt

@ Wrenchbender-that's what I'm hoping. I was more concerned about the little "hidden" things that might make them incompatible.

@ Kurt-I saw that list too, but it is definitely stamped with 966S and is definitely manual choke. I wonder if it was put together from different carbs before I got it. Oh well. It doesn't matter, as long as I can get them to work together.

They are replacements for a 235. If you put two 235 carbs on your 235 you will be over carbed. I know from experience. Right now I am trying to get my Carter W1's rebuilt and moded to fit my manifold. You want two matching carbs. They need to come from a 216 engine in order to not over carb your 235. Clear as mud right?

Having dual Carters on my truck, I'm a believer in rebuilding two carbs together to ensure they are setup exactly the same. However, if you can confirm they are jetted the same and the ventur's are identical, here is how I'd set them up. I would install the one with the auto choke in the rear. I would remove the butterfly from the manual choke so that it can never choke. Make sure you get a Uni-Syn tool to make the carbs play nice together.

@Apache-Have you done any other mods to your engine? I've upgraded my cam, exhaust and ignition. It's just waiting for upgraded fuel delivery...

@Sweet-That's just my plan to only have one choke. I was going to put the auto choke one on front, though, to put it closer to the manifold heat stove. Just wondering why you would go with the rear. Is there something else I'm missing?

Thanks for all of the replies so far!

They're a bit big. If you have a tall axle ratio, low numerical 1st gear, heavy chassis etc. you may not like the day-to-day operation in traffic.
I'd look for a pair of smaller carbs.

I have Fenton Dual Exhaust, pertronix electronic ignition and a custom Cam from Clay Smith Cams.


With the larger carbs on there, it would stumble of idle, unless I had it idle kind high. I had great power and response in the higher RPM's in 2nd and 3rd.