The target AFR during light acceleration is a great question, and one which I don't have any firm thoughts on. It should certainly be leaner than WOT AFR. There is not much load during light acceleration, and I would be too surprised if keeping it around 14.7 is acceptable. The best answer is probably to see what a modern factory EFI system does. Does anyone have insight into that?
I asked about the AFR immediately following a gear shift because on my car I have noticed a significant transitory lean condition after a shift on light acceleration. Its almost like the carb looses its metering ability for an instant when the RPMs drop. I'm not that concerned about it, but when the motor is not to full operating temp, I can actually feel it go lean (besides seeing it on the wideband).
I'm sure you're frustrated with the wideband problems. I know a guy whose LC-1 went wacky during a road race, but hadn't heard what the final resolution was.
I'm not sure if the different progressive ratio on secondaries will make much difference on the AFR. When going to WOT, the difference in opening time between primary and secondary is going to be pretty darn close. I thought the advantage of the different ratio was during moderate throttle conditions, where avoiding hitting the secondary accelerator pump can help. The VS secondary carb likely had a much more noticeable difference in timing of opening between pri and sec, and obviously doesn't have the extra fuel from a secondary accelerator pump.
Your accelerator pump cam tests sound like they are going in the right direction, and this "knob" will likely get you to where you want with sufficient experiments.
I don't have a lot of info to share on pump cam affects. On my motor, virtually all of the cams have been insufficient, with a big lean spike on the WOT transition. I have had to go to the biggest cam (blue) and currently have a 0.035 squirter. I purchased a 50cc pump, but unfortunately it has interference with the RPM DP, so for now I am sticking with the 30cc pump. My WOT AFR still needs tuning, and is a bit on the rich side. I'm trying to strike a balance between high speed cruise and WOT mixture and am still playing with the PCVR and main jet relationship.
