The oil temp measured as close to the rear main oil gallery as possible
should be 210 or below. That is because the bearing overlay material is
loosing strength with higher temps. This is a rule developed based on
racing, (Racing Beat) where RPMs will be around 9,000 for 13Bs. Or 9,500 for
12As. Bearing stress is lower around 6,500 RPM. Still, it's not a bad idea to
Keep the oil well under 200 degrees. The engine builder reports power lost
Above 160 degrees on the oil temp. Water under 200 is OK. Power loss above 180,
But no damage.