I'm not sure which 2 barrel either one of you guys are using. You are either using the wrong port or your throttle blades are open too far at idle.
The first thing I would look at is the timing. Assuming that you have already done that, I say you need to check the timing mark on the damper pully. You have to be 100% confident that this mark has not moved. These dampers go bad more often than on most engines because the belts are on the outer ring of the damper. The belts, the alternator, the fan, the water pump are all tugging on that ring and trying to make it break loose. On most V8's the pullys are bolted to the front on the inner part of the damper.
