While I am the first to admit the engine in this car is built as if intended for battle service.
But, engines are a funny beast, they have a tendency to show attitude in areas refered to as "Red Lines".
running under a load at red line can sometimes keep an engine running better than just free wheeling and then just the opposite happens the slightest touch or kiss of a valve against a piston and ther is nothing left.
Have I answered your question? Absolutly not, but I did a fine dance around.
My guess, much higher than the indicated red line and at top end I doubt we would have to worry about it.
Mike