No. Running anything commonly available at under 100 octane is the culprit. Good fuel = good horsepower and great torque under any loads in all conditions without any pre-det even with high advance timing numbers and split overlap(100/105C) cam timing. 93 pump gas with a shitload of canned octane boost will get me home in a pinch if I can't find a racetrack(or friendly airport) nearby to fill her up. Still sounds like a coffee can with about a handful of steelies being shaken violently if it's hot and humid out and I get rev/torque happy with the throttle. It's more a result of intake air temp and density than it is the actual engine temps. My compromise so that I could enjoy riding it on the street was to decrease the squish by increasing chamber volume and dialing the static ignition timing to the OE stop(-15 to -18) on the retard side. I learned the hard, expensive, and time consuming way that pumping a 25+ year old air cooled mill up into the performance output range of a Blackbird was possible, just not very practical. But again, I'm sure that the computer will cure nearly all ills but may never reveal what the potential output could be if we had something besides watered down Zippo fuel available at the local gas stations...