Chancey;
Air time and runs will differ a bit from bench running. Centrifugal force affects the fuel flow. Start off with a two ounce tank and see what the run time is. If it's too long, use a small syringe to measure a precise amount of fuel for what we refer to as "short tanking" an engine run. I always put is a larger tank than I think I need, about 25 to 30 percent more if possible. Air temperature affects run time, colder air requires more fuel, and shorter runs, warmer air less fuel and longer runs. Use a stop watch to time the runs as closely as you can. once you become familiar with the drill, is becomes second nature, Knowing how long it will run on a specific amount of fuel and paying attention to your watch will let you know when you are almost out of fuel and you won't have enough for one more loop or wing over. That can save you an airplane when the engine quits when you don't want it too!
Type at you later,
Dan McEntee