Like George, I'm not fmiliar with that model. But making a couple of assumptions...For sport CL flying, with a model of a finished weight of 16-20 ounces, the OS LA 15 is a lovely motor. My son flies the wheels off his 15 size planes with the LA. Don't transfer your RC experience directly across, because RC and CL are pretty different in terms of the kind of power you need. If you buy a hot BB Schneurle engine and set it to scream. it'll twist you right into the ground. Is this the model you bought? It's cute and would probably convert to CL OK. And at the stated weight (minus the weight of the radio gear), the LA 15 would be perfect and cheap.

Viper
Sport Electric ARTF
Wing span 1000mm (39”) - Wing area 17 sq.dm. (240sq.in.) - Length 700mm (27”) - Weight 700g (1.6lbs) - Motor included 400 geared - Radio required 4 channel - 22 amp speed controller required - Power required 8.4v 800mAh nicad

Viper Sport Electric ARTF
click image to enlarge

Factory built and covered fuselage including cockpit detail, 400 geared motor included and fitted. Vacuum formed clear cowl. Wire undercarriage with wheels. One piece built and covered wing. This sport electric model certainly looks the part. The model even comes with propeller and extra gears.