Wouldn't really matter 1130 or 1250 but no engine would last 500 at max rpm. I'm sure they chose a good mid rpm for that. What that is, I'm not sure we will ever know.we know that the 1130 engine past the Düsseldorf Test but did the 1250?
only the 1130 is in the porsche museum.
also the test is done on a dyno for 500 hours is it at redline for the full 500 hours?