ro347: I fly in Moonachie at the Hackensack Valley Flyers.

I have an O.S. 1.60FX in my GP Su-31 which weighs about 11.5 pounds fueled. I can get (I sh*t you not) about a 17 minute flight (full 3D) out of that engine and the stock tank and have time to spare. I set my timer for 8 minutes and land with half a tank and I have the motor set rich. Like Mr67Stang says, you will be very surprised at how miserly it sips fuel. YS's are powerhouses but they gulp fuel.