I ran some 110 leaded with the 509 cam setup. It ran fine with zero detonation. The thing is, a few years back, it ran fine on 91 with the same timing. Maybe some of that is due to the ethanol in the fuel, but I wonder if most lies in this carburetor.

Converter stall speed? Sorta hard to tell. Its a 9 3/4" unit that was built to be a 3000 stall. I didn't like the lazy way it felt so I had the builder cut it open and change a few parts inside. It stalls lower than that now.
When I'm stationary in gear holding the brake, it will start spinning the tires on concrete at around 2200 or so. Asphalt would probably be higher.