In my experience you could tell when the material is starting to get hot because the clutch turns into a chattering light switch LOL. That is usually my cue to give things a cool down.
3 seasons on 150-175 Monte Smith plate kit + street driving all summer. I had to really abuse the clutch for the duration of last season because we added 150hp n/a. Ram Powergrip HD rated to 650rwhp.