There is some pretty good information on Mike’s Carburetors website. I’m not sure it’s all there. Some info I found in the internet. There is some info towards the end of this AFB site, but as someone said, original AVS stuff was 3-step on the primaries.
https://www.crankshaftcoalition.com/wiki/images/2/2e/Carterafbtuning.pdf
https://www.crankshaftcoalition.com/wiki/images/2/2e/Carterafbtuning.pdf














