Castle Creations recommendations for the Losi Super Baja Rey:

Castle does not currently offer a motor that will fit the Super Baja Rey and still be powerful enough.

The 1717 series is not strong enough and the 2028 series is too large.

The Mamba Monster X 8s ESC is a solid replacement for the stock ESC and ran with the stock motor.

The Cobra 5 can also be used, but is a bit overkill for the stock motor.