First thanks for the info, second my Siato 100 was purchased used with the extra and has never produced long flights. It had a 15x6 prop, and I will have to check the tank size. In the end though a 6min flight was pushing it. In its last flight the engine died on take off after a nice warm up and was running just fine on the ground. This is on a plane that had been flown a bit with no issue. I may try to bench test the engine, but also want to try gas.

Thanks for pointing out the weight difference and I will have to check how much nose weight is on the plane I have I believe it is a bit, but doubt its enough to double the engine weight.

What size are the new gas engines coming out?