Here is the carb that is on my 235. I am wanting to match one or two to it. I think the circle off the side is the auto choke. Do I need to get the other carbs in this same style? My ultimate goal is to run fentons and at least a dual car setup, maybe even the triple. Are there provisions in the manifolds for three heat hook ups? The carb base number is 7003536
You could try Tom Langdon's Stovebolt Engine company, he used to have triple carb. set-ups for 235/261 engines. However, you need to be careful that the last carb. in line clears the firewall (at least on a truck). That's why a lot of people don't use the triple carb set-up. I used a dual carb Fenton intake with 2bbl adapters and Holley-Webers. I purchased it all from Tom and he was very helpful and knowledgeable.
With the larger air horn and 90 degree fuel line, that carb is a '58 or newer. You do not need or want auto choke working on more than one carb. If you are going to try to match that carb, you need to make some measurements on it to compare to any that you are planning on buying. They made many versions of that carb over the years....
If you flip your carb upside down and clean off the gasket surface, it may have the last four digits of the I.D. tag number stamped in it. I've seen several that did.
This article may prove useful when trying to match internal components: http://www.inliners.org/tech/tech4.html
The motor numbers as a 1958-1959 235 so that would make sense, however I thought it was from a truck.
but if your just driving it as a daily driver, why would you want to mess that up with more than one carb. seems like alot of headache for not much gain. good luck!
I have read more then one place that adding that second carb dose improve the motor. Is that not the case?
If you are referring to manifold heat, there will be just the one hook up, regardless of the number of carbs. If you go with the Fenton exhausts (or other headers), there will be no exhaust manifold heat box. In this case, heat is transferred via tubing from the header to a "heat plate", which bolts to the bottom of the intake manifold. The Fentons come with threaded bosses for these tubes, which must be plugged if manifold heat is not run. The heat plate is purchased separately ($35.00-$70.00). Though rare, some vintage intake manifolds were water heated (Edmunds, et.al.). Additionally, others have no heat box/plate provision (Ellis, et.al.) Once again, these are quite rare.
BIG IMPROVEMENT! Dyno tests show 10-15% horsepower improvement or more, even on stock engines. I know of no other single modification that will provide a more cost effective improvement to any engine. (Fuel distribution is a key factor here.)
It's definitely the most important single modification you can make to a 235. It got me nothing from 0-40, but it got me a lot from 40 on up, and better mileage to boot.
Personnally, If I were running dual Rochester B's, I'd be looking for a pair of manual choke truck carbs from '54-57. If I needed the smaller bolt pattern (216 intake), I'd be looking for '50-53 216 manual choke B's. Just FYI, The spun aluminum 6" air cleaners that Tom Langdon sells can be had with the smaller air horn. You have to call and ask for them. More FYI, The 216 and 235 have different carb bolt spacing. Some dual & triple intakes were made for one or the other, so you need to be aware of this before buying, so you can be sure your carbs will bolt to the intake. It dosn't matter which setup you use, as you can get adapter rings to match up the intake ports. If you are running Fenton exhaust manifolds, then the mating flange between the manifolds isn't an issue, but you try to use the stock exhaust with the aftermarket intake, you need to make sure you have the right exhaust manifold as the flange angles are different between the 216 and 235.
This has been my experience as well. I had a 1k trip earlier this year and averaged 18.7 mpg going 60 almost 80 on that tankful. My two Carter-Webers that came from Langdon are well mannered and add fun to driving.
Yup that "circle thing" is an automatic choke. Beware buying one barrel Rochesters off Ebag, most come with a worn throttle shaft bore. Nobody makes a repair kit I know of. I'm thinking of trying a 4 barrel Rochester throttle shaft repair kit on the carbs I have.
Mo, As for heating the intake, you are correct, but Voh was asking about heat for the choke, not the intake. On the front half of the newer Fentons, there is a small blind hole for the choke tubing to plug into....
If anyone is interested - this is what I did to the firewall to get a third carb to fit my '53. Also note, the outer carbs are blocked for now as I work on the body. I'll mess with getting them all to play nice together over the winter.
I'm finishing up a design for progressive tripower linkage. All stainless steel. not cheap, but it works great!
Does anyone know what the CFM rating was for a Roch 1BC off of a 58 - 62 Chevy p***enger car or truck is? Looking to go with either a 2 x 1 or maybe a 3 x 1 setup on my 55 1/2 ton. Want to match things up with the cam, head, and headers.
A 235 has to be built pretty stiff to justify three carbs, and the gain over two carbs is negligible. Yeah, I know, three pots look hotter! I'll stick with two on my street six.
Overcarburation is what I'm worried about. However, to know for sure how many carbs to run, the CFM rating is needed. I've looked in carb books, factory shop manuals, and parts books. Still haven't been able to find this info. By the way....My 235 is bored .060 over, with about 8 1/2 compression. The head is from a 62 Impala, (848 head), which has been ported, and polished, with the valve guides cut down, and hardened valve seats. It has a Mallory Unilite and a set of Clifford tube headers. The cam is an Isky E-2 with a cam lift of .298, valve lift of .448, duration of 264, and duration at .050 of 228. The engine has also been balanced. I used to have a Clifford 4bbl intake on it, but the fuel distribution was not very good. The end cylinders tended to run lean, while the center cylinders ran rich. I would think that a 3 x 1 setup would be the best design to fix the rich / lean problem, but overcarburation is a concern.
My full-pressure 216 (9.1:1 C.R., cam, headwork, etc.) will be running a water heated Edmunds 2x2 manifold with Holley 94's. The throttle shafts will be split for two-stage operation. The right venturies will be primaries, while the left venturies will open at about half throttle, via adjustable progressive linkage.
You are correct, Sir! Although I think the plenum on the Edmunds will help with the uneven intake pulses of the paired cylinders (compared to the Harper). 2 twos will definitely be enough carburetion, for even a hot 216 !
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