Rochester model B manual choke carbs from the mid 50's.
When you plug off the idle circuit, you will also need to make the throttle plate close completely, otherwise you will be pulling air in without any fuel mixed with it and you will get a lean condition and probable surging.
If you study a genuine set of tripower 2 bbl carbs, you will see there is no power valve or idle cicuit in them. I used this info and applied it to the "B" carbs, as they are basically the same design as the 2GC 2bbl. The problem with a vaccuum operated power valve is that when you add more carbs, you change the vac signal that the power valve sees. Nobody offers lighter springs for these carbs, so you have no way to adjust for a change in vac signal. A larger cam can also add to this problem. Luckily, by removing the spring, valve, and the spring loaded ball above the jet, you no longer need to worry about it! Basically you end up with the secondaries of a 4 bbl carb. It's my understanding that by using a carb like the Carter W-1 or WA-1, you should be able to leave the carbs alone and just hook up the linkage as needed, but I haven't tried this way yet.
