There has been some discussion in this thread about alternatives to the Rochester B. Lets do a bit of discussion. The MAJOR carburetor manufacturers in the USA in the last 70 or so years would be, in alphabetic order: Autolite (a.k.a. Motorcraft), Carter, Holley, Rochester, Stromberg, and Zenith.
Autolite - the common single barrel Autolite is the 1100. I don't know enough about these to discuss their dquality / reliability, as technical data on these is as difficult to find as an honest politician; not impossible, just very difficult. I would suggest their use ONLY on OE applications for this reason.
Carter - made a number of different carburetor series: AS, BB, BBR, RBS, W, and Y. I am personally partial to most Carters because of a number of reasons: initial cost, availability of documentation, availability of parts, and quality (specifically the W and Y series). I would suggest ignoring the existence of the other 4 series. I have pitched the YF and W-1 for decades due to the above parameters.
Holley - made a number of 1 barrel carbs; common ones would be the 1904, 1908, and 1920. I do not personally care for the side-bowl design. I will not discuss these, other than to mention their existence. If others wish to chime in, be my guest.
Rochester - made the B series and the M series, as well as the side-draft R series.
Stromberg - made the A series, and the B series. It may be argued that the Stromberg was the highest quality of material and manufacture. Ignore the A series completely. There are a number of variations of the B series, all of which are good carburetors; one just needs to pick one with the internal venturi best for the application. Parts are readily available by mail order, documentation is available, costs are greater than Carter.
Zenith - made a LOT of different downdraft carburetors. The series to use would be the 28 or preferably the 228. Documentation is available, but you may have to pay for it. Parts are mostly readily available for mail order, but expensive. Quality is probably somewhere between Carter and Stromberg. Unfortunately, one can no long buy new Zenith carbs and parts from the manufacturer. All you folks buying the Chinese stuff should be proud, we lost another quality American manufacturer (and American jobs) at the end of 2025. For the ultimate single carb installation, Zenith is probably the best bet, as many different internal venturii sizes are available.
Note that I have not, nor will I discuss the modern import stuff, or the lesser known American manufacturers such as Fish.
Fuel injection - not my cup of tea; if someone else wishes to chime in, do so. I will say that my dual quad 1968 non-Chevrolet truck with 450 HP gets better fuel economy than my 1998 150 HP V-6 fuel injected non-Chevrolet truck.
Multiple carburetion - lots of pixels have been disturbed on this subject. (Opinion) If you don't already have a setup and you want a setup, look at a 3 carb manifold rather than a 2 carb manifold for the Chevrolet 6. Not saying 2 cannot be made to work. Am saying that 3 will work better.
Now, what would I use (if I had a Chevrolet 6) ?
Easy - for a single carb application I would do the math, and acquire the proper Zenith carb. But if I was not FORCED to use a single carb application, I would acquire a 3 carb intake, and run either 3 of the Carter YH sidedraft carbs (235 Corvette) or 3 Carter type W-0 carbs if I wanted downdraft (sorry Jerry).
Costs - have different meanings to different folks. I personally would rather spend more money on a quality item than more time trying to make a cheaper and inferior item work. Again, my opinion only. How much is your time worth ?
Jon
