I have a lot of Super Tigre G-65 time in Class 2, won a lot of contests with them . My best luck is with the large bore Kavan Pressure Carburetor running crank case pressure from the upper left rear cover screw port, not the timed port on the rear cover below the rotor pin., I made an exhaust baffle that connects to the carb . I used 60% Nitro for performance, better idle and throttle response. I also spent a lot of Test Stand Time teaching them how to perform with reliability.