Sorry about that - you must use the drive up window a lot. Glen says a choke is a pain, but a jammed automatic choke is a common problem, not recoganized as a problem and usually rates low on the priority list. Back to your original question: with all the expertise you exude on "porting", why would you not immediately consider a 4 barrel carburetor and manifold as a matter of a pragmatic upgrade? At least at that time, your modified 4100 can be easily swapped for a non-modified one, or replaced by another type. Remember - "Speed costs money, how fast can you afford to go".