This is a factory 350 TBI. It has 2 injectors and a dual plane manifold, one injector to each plenum. this is a rebuild of an engine that fragged on the interstate. I replaced the longblock but the manifold and intake stayed. There is just a standard steel stamped key. Theoretically the only thing that has changed is the cam affecting cylinder pressure and fuel charge in the cylinder. The distributor makes spark to the #1 lead on the compression stroke. I checked this by pulling both the spark plug and the valve cover and then turning the crank to where I wanted it. I disconnect the single wire connector called for. With a plug in the #1 wire I rotate the distributor to the point where it sparks. I have thus effectively checked my static timing.
I am leaning toward denny's suggestion of overfueling. I think I got it flooded early and have been fighting with it all day. I need to keep an eye out for fuel wash and go back to basics.