Keep in mind that the victa motors are solely piston port timed.
Performance is limited by that.
Engine is designed for a task and does it admirably. Victa full crank motors were all the go for carts years back. I would be looking for an old school small engine machinist, im sure there would be a few tricks that you could pick up there.
A Colt ride on would be the go. Put the Victa motor on it. Start modifying.