I just put on dual quads, due to my single carter being bad (I thought) The car would start great then Die!!!

Here's the specs
I have 2 brand new carter 500s, electric fuel pump set at 4.5 LBS, petronics one ignition, Newly built, and balanced engine.

Any suggestions

I've been wanting to do the same conversion to my '64 Riv. I'm not a master mechanic but the people I've spoken to about this tell me that the dual quad engines have different distributor specs and and a different cam.