i would personally get a higher performance 40-50 size motor. supertigre g-51 is a nice priced motor, and puts out a lot of power with good fuel economy. its what i used in my trainer and would make it go straight up and take off in about 15 feet tops. i orginally had a os .40la in my trainer and the g-51 put out a LOT more power and made flying a lot more fun. You could also go with the 46ax which is comparable to the g-51 but a little more pricey. the .46la wont put out that much more power than the .40la and weighs more. just my opinnion.