Maybe the combo of corked up exhaust and small carb, new cam just didn't like it? Tail pipes used to choke down the smaller cam, probably worse with new cam
My opinion, carb is not too small..........what size primaries on headers, collector, and remaining exhaust system? To have hurt that much, you would have had to shrink the system..........as an example, I run 1 5/8 primary tubes, 2 1/2 inch collectors, 2 1/2 inch pipe to mufflers with 2 1/2 inch in and out. If your exhaust system is equal to or larger then that at any point, exhaust is NOT your problem.
I know this is a some what silly question........did you make sure your carb went fully open when you stood on the gas pedal? Goes along with did the cable slip in the clamp.
