Thermodynamcally, your not gaining anything.
You're using a device to remove heat from the motor which in turn needs to have the heat removed from it as well. All this while using power from the batteries that power the motor or other batteries on board that require extra power from the motor to carry the weight.
In the short run you would gain power from a cooler motor but in the long run all the losses from keeping it cool catches up. Unless you can prove that the power gained is so tremendous such that it outperforms the power lost.