So I want the best performance for my off road go kart and I need to know if my engine should spin the axle which spins the tires or have the engine turn one tire
The general rule is for off road use, a live axle is best (2 wheel drive), as it gives good traction and the dirt allows the tires to slip a little, making turning easier.
A dead axle (1 wheel drive) is best for on road use.
Yea it best to go live axle i just finished building a fixed axle kart with 10hp OHV engines with 5.4 gear ratio and it push hard to the right side when i hit the gas pedal and throw dirt everywhere with 13 inch tires