[BrianG]

Covering the holes does limit cooling, but you gotta remember these motors were designed for aircraft where you have a huge fan (propeller) blowing air into/across the motor. In cars, you just have whatever flow makes its way under the body, so the vents play less of a role.

I use aluminum tape on the wire end and cut a thin aluminum disc to sandwich between the motor and mount in front. I use aluminum because it help transfer the heat to the mount. In the three Medusa setups I have (one of which is a 36-80 on 5s in a XT8 truggy), everything is fine temp-wise. Eventually, I plan on getting the heatsink clamps Mike is working on just for added insurance, but it probably isn't required.