Can't say; only had stock gauges, and that was about 20years ago.
But it was hot enough to lock up immediately at shut down, and requiring 30 minutes to cool enough that the starter could crank it again.
That winter, during the annual freshening, I had the cylinders honed out a bit, replaced the rings with file-fits, and opened up the ring gaps about .005 .. With the other changes I made, the Problem was solved. The KB107s survived just fine, and are still in there. So my diagnoses was that the ring-gaps were just too tight.
