1969RR, please let us know what you found that is causing the problem. I have an almost identical setup, except I am running a single 850 Demon carb. With bad gas and a screwed up carb we got just shy of 600hp and 630 tq on the dyno. It is a torque monster on the street. While I was experimenting with different carbs; I did experience something similiar to what you are describing. It was gutless and when I came back and pulled the plugs they were all soot black and wet. I shelved the carb, motored the engine over, changed plugs and reinstalled the original carb and everything was back to normal.