Just reading the 1976 FSM manual here and it explains the manifold heat control valve (passenger side exhaust manifold) and what it does. Just as I thought, they still used them at least way up in to the late 70's. So the chokes (thermoquad) in question were getting as much engine heat transfer as did a 1969 383HP Roadrunner with an AVS and no electrical assit on the choke opening. Now I dont want to piss in your Wheaties or anything and I do understand what they were trying to do by getting the choke off quicker in hot enviroments, but I still hold true to the fact that you dont need them. If its something you would like to "tinker" with for peace of mind and perfection go for it. I get that, I really do. Does the orignal poster need it to make his choke "work"? No it will still open and close all the way with just engine heat transfer. Heres the explanation for the electric assist choke system in question out of the 1976 FSM below.