After market flywheel mismatch chatter

I was wondering if any of you have ran an after market flywheel weighing about 9 pounds roughly (make of chromoly) on your B-series trannies. The reason why I’m asking is that ever since I got mine installed, it seemed to have gotten worse and worse. When start the carnow, I would say 35% of the time, it’ll make a spinning chattery sound and won’t start. My friend who works at the shop told me that the teeth on the flywheel isn’t matching up with the starter. He says that it’ll only get worse. Is this true? It seems to only affect the aftermarket flywheels, and not the stocks one. What can I do about this situation?