[Scott65]

I think if you can keep the #8 line full under all conditions, it should be enough. Maybe pull the lines off the carb and do a flow check post regulator? See if the results make sense for 100gph through the system, or if it's less. As for the transition lean spot, I've never dealt with alky carbs. My only experience is with EFI. I'd ask the question have you increased timing any for the E85 set up? And are you sure it's a lean stumble, and not related to needing some more timing? Also, I edited an earlier post, not sure if you saw it, don't forget about stoich for e85 being in the 9.7 range. You mentioned earlier shooting for 11.8-12 and that may hurt something.