There are some great kits around now that will convert to slot cars, 1:32 trucks are huge but great fun to drive.  With the very large tyres and all that weight you’ll need something that gears down the motor, this is it and this is how to build it.

Put the long can motor in position with its wires soldered into place and the black pinion on the motor shaft.  The layshaft has the large black (sidewinder) gear on one end, bearings in the middle and the white pinion as shown.

Rear axle next, put on the contrate gear and bearings.

Then fit the layshaft.  Add some glue to hold the gears onto the shaft

And finally the rear axle

This is how it should drive!