What will it take to overheat A victor?

[BlackShadowFox]

For some time i have been testing different ways on mounting victors and came upon two questions: (This would be with the normal power levels of the robotics competition)

1. How much could i contain/surround the victors venting before they overheat? or lose a great deal efficiency or even destroy them?

In the Victor 884 user manual they only state this:
"The speed controller must have adequate space
above the fan for airflow, a minimum of 2 inches."

The second question is if the victor does overheat then would the victor shut it self down till a suitable temperature is reached?

Please don't post stupid and obvious things such as "If you put a plate over the fan then it would overheat, or covering up all the venting" for these are obvious