Yeh, might as well try what you already own. Stay with the 13's. A torque converter would probably be cheaper than 2 smaller tires, and then you could run the 16's with no problem. For driving with the centrifugal clutch try to lay out a course ahead of time where your kids can just take off and go. A lot of stop and start driving ( like when you are not sure where you're going ) or also a lot of low speed part throttle cruising will cause the clutch to fail. Get in, nail the gas, keep it there, and drive. For letting the kids out into the woods and kinda hunt and peck and find their way a torque converter CAN'T be beat.