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Would a Rochester B with heated air choke fit in place of a Rochester RP? The 'B' is said to be used for a 235 w/ Powerglide and the 'RP' is being used on a 1959 261. I am going to a dual carb setup on the 261 and wandered what difference there was b/t the carbs other than the choke device. Thanks.

All the B's have the same design,but there are differences in the main jets, easy to change, and differences in the airbleeds,off idle transition ports and power valve flow, these things are not easy to change.
If you intend to use daul carbs, try to get a pair with the same specifications.
B's often have troublesome fuel leaks,you might try for Carter or Holley single barrels if you aren't dead set on using the Rochesters.

Are the troublesome leaks due to age/need of rebuild or poor design? Someone is selling a set of three and I thought it might be a good idea to make an offer if they would work on my setup. How necessary is it to swap out the ports and valves? What do they affect and would it render my truck undriveable? These carbs are all the same specs, which is what intrigued me.

As long as the carbs orignally came off the same type of engine,50's Powerglide 235 for example, they should be close enough in specification.
I had dual Rochesters on my 261,they didn't leak from the bowl gasket like most, but on hard acceleration, fuel dripped down the accelerator shafts onto the manifold.But in my case, the Rochesters carburetored quite nicely on a heated manifold.The stock main jets in mine were fine, I believe the jets were #56's

where would you be able to find main jet sets? NAPA or similar places? What are your thoughts on the difference b/t the manual choke setup and the air choke? Is the air choke the same as an automatic choke?

You can find main jets online, do a Google search for Rochester Carburetor parts.Yes, auto choke is a hot air choke.If the carbs have the correct ID tag still attached,that will tell you the application.

i've never really had many problem with the rochester B, but then again, i don't watch the engine while i drive. what is the deal with them leaking? and is there anyway to fix it? they're readily available...so...it just sorta makes sense. right?

sorry if i stole your post shane.

Sam.

I understand that worn bushings on the throttle shaft causes this leaking. This is a typical issue with well-used rochester carbs I think.

The worn bushings cause them to leak gas and also to suck in air. I've been told that the local lawn mower or electric motor suppy stores have suitable bushings. You need bushings that will fit your throttle shaft and that are a little larger then the shaft holes in the bottom carburetor plate. Then you have to take these parts to a local machine shop to fix the carb.

I haven't done this, but my original Rochester carb leaks here, and I'd like to repair it. The rochester carb works fine on my 235 - notwithstanding the detractors out there.

I have a HTML detailing this repair with pictures. It's for a different carb, but I bet this job is generic. If anyone thinks it helpful - I'll post the HTML on my server.

I'd like to hear from others who have done this repair - it would be really useful to a lot of us.

Thanks for all the input Guys. I have not quite decided if I am going to stick with the 'B' setup or go with something else. I sat on the phone for about 15 minutes with Tom Langdon today and talked about the Holley Weber carb that he sells. I could put the 1bbl to 2bbl adaptor and mate it to my 2x1 Fenton intake pretty easily. Problem is, it's going to cost me. You know the story. Sounds like a great setup, just don't know if it's worth taking a hit in the budget to sidestep a few potential landmines in the future.