RE: Looking for a WACO kit
The plane will fly fine on an OS 108. or an OS 120 size 2 stroker. If you want a Jimmy Franklin type flight then yes, you will probably need more power. But with the aforementioned engines the plane will do loops, stall turns, etc. The Army used them during WWII as a trainer along side the Stearman. They were designed for mild aerobatics.