This method definitely works. Just make sure to use good bags that don't leak. I did this to a friend's stock motor at the Cleveland Champs a few years ago. He was on TQ pace in the last qualifier when the motor tag fell out a few laps from the end after a collision with some cars that had crashed in the sweeper.
Investigation showed that the tag had gotten wet due to the bag leaking and then the tag shrunk when the motor got hot during the run. The collision flung it out of the arm and jammed in between the arm and magnets. We were able to duplicate this to confirm our suspicion with another motor that had soaked with his.
However, the motors were completely submerged in the leaky bag for over 7 hours so that probably was the biggest impact on the tag. I do not know if that would be an issue if the tags had not been drenched for a shorter time.
Originally Posted by EddieO
Or, just toss it in a plastic bag and put iti n a cooler with ice or the fridge....run for about 10 seconds before you toss in the car.....way colder than any spray or peltier cooler ever will....