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My daily driver is a '59 Apache that I recently put a 250 ci motor out of a '67 Chevy II in. I got close to 16 mpg on a 200 mile trip last Saturday. I am thinking of replacing the stock 1 barrel carb with a webber 32/36 progressive 2 barrel carb. Has anyone else done this and what kind of improvements did you get? I have read that you should get an increase in hp and mpg. I would like to get better mileage and would not be opposed to more power either.
Thanks a lot,
Gene

I'm running two 32/36s on my 261 ci inline and they are great, just a 4 barrel split in two, not sure one alone would do so good. I put a 4 barrel/offy intake on my old Nova 194ci six and WOW she really responded and got good milage as well. I'd do the 4 barrel again in a minute.

Best of luck
Jim

Jim
Thanks for the response. I will probably do some more research before I get the carb. I would like to talk to someone that has the one carburetor setup and is not a dealer to get their opinion.
Thanks again,
Gene

What is the CFM of the carburetor?

What is the expected CFM of your engine/set-up?

I checked the cfm rating for the 32/36 and I get mixed responses but it should be somewhere between 255 and 300. The Rochester B that is on there should be around 250. I intend to use an adapter to fit it to my stock manifold. I don't really understand this sort of thing so I can't answer your 2nd question. I am thinking that when I am putting around I should get better mileage as 1 barrel would be like a smaller carb than the Rochester and when I open it up it would be like a bigger carb and have more power. Am I thinking right?

I am trying to figure out the same things as you are, Gene.

Your reasoning looks good to me.

Guys, I'm gonna put my 2 cents worth in here. I have a .060 over 261 whith a howards m4f cam from Patricks, fenton headers. It's a 59 model full pressure motor, I have run it with the roch. model B. It runs ok. With a holley weber from Tom Langdon, gets good mileage but lacks midrange power and kind of lacking on top end. Have run rochester monojet and it runs much better pulls stronger through the whole range, especially mid to top end. I don't know about the cfm ratings, just my observations from running different carbs.

Tommy,

What model/year/engine Rochester monojet?

Had a monojet on mine(235), then put on the correct rochesterB on. It is exactly as you say mid and top end went away, I'd dare sy mono has to be a third bigger in cfm. I know the stock oil bath air cleaner is too small to fit it. It is just a bigger animal.

It sure would be helpful for those of us who know very little about carburetors if you would tell us carburetor model/number and the year/engine it came off of.

Thanks,

Tim, sorry I wasn't near computer yesterday evening. The monojet was off of a 1970 nove with a 250 cubic inch engine.

Tim, sorry I wasn't near computer yesterday evening. The monojet was off of a 1970 nova with a 250 cubic inch engine. I will try to see the model number later today or tomorrow, am not near the truck at the momont.

Thanks, Tommy

Since you're not worried about originality, you might want to try a Carter YF from a mid 1970s Ford 300 L6. You also get electric choke, too.

Best wishes,

Les

Tim,

The numbers are off of three different carbs that I ran. I believe they were off of a 70-72 nova that I had many moons ago.

7040025 17058007 7044321

11y 0 lr 332 7 bdr 338 3 al

Hope that gives you something .

I hate this computer

7040025 / 11y 0 lr second set of numbers are under the first set on the float bowl.

17058007/ 332 7 bdr

7044321/ 338 3 AL