Hi Chris,
Different Jon here. If you want to see the work/study on the warped Rochester castings, you might search using "straightening Rochester castings". Based on what I saw, every Rochester B or BC will have a warped casting to one degree or another. There is also some information on the power circuit/power piston and the problems caused by loss of vacuum, inadequate vacuum, etc to that part of the carburetor and the effect it will have on the rich/lean condition.
The Carter I'm using on my 235 does run much leaner and more well mannered than the Rochester did by the way.
