I rebuilt both carbs. The diaphragms are new and the slides seem to function as they should. The float height is, I believe set correctly, the floats are about a year old and float at the height of the pins, as they should.
Negative G's have an immediate effect, so I think that rules out a float problem. It would normally take some time to use up the fuel in the bowls. If the pistons were moving upwards with negative G's I think that would reduce the air velocity in the venturi and cause a lean mixture. But why no improvement with new diaphragms?
I do have another set of carbs that someone lent me to try. I have been hesitant to try them so far because I have the pressed on carb heaters and these do not. I would need to plug the coolant lines going to my heaters and pick a day when carb ice wouldn't be a concern.
