I have a 71 240z w/ L28 n42 head all stock. Triple solex c40, cannon manifold,square port headers. Electronic dizzy. Adjusted the valves to spec(cold). Then try to sync the carbs. 5 and 6 cylinders not enough vacuum like 1-4. So I decided to run fuel line direct from fuel pump to first set of carbs and then daisy chained to the other 2 carbs. No fuel return line.
I have to hold the choke cable and adjust to idle speed. If I open the choke all the way. The idle will jump up to like 5k rpms and the header will turn bright cherry red. I would then have to shut off the engine. Mind you the dizzy is @ full retard. What would cause that sudden surge from 1.2k rpms to skyrocket? Please any advice would be appreciated.