If I changed my ignition system, I would start tuning my carbs from scratch. It does not matter much what the ignition curve looks like, as long as it does not change after you have tuned the carbs. I run a Boyer with fixed timing. If I ever have to disturb the pick-up rotor, I always carefully check that the jetting is still right. A small change in ignition timing can have a big effect on the required jetting.