Yeah, tell me about it!! I've been doing some tuning with WR O2 and found that as jetted, the left and right banks are about 1.5 AF different. Also running leaner in the boat than what Tylers dyno sheets show. Managed to get 64mph out of it with some rejetting, but I have to stagger the jets side to side quite a bit which doesn't make much sense on a single plane manifold.

Still hits 60 pretty early in the throttle and then takes every bit of the secondaries to go from 60 to 64.

Single plane intakes not having equal flow doesn't surprize me. We have had flow work done on various single plane intakes, all have had to be re-balanced.