I've only had it on the dyno so far, I'm still waiting for a Quicktime bellhousing before I can put this motor into the car. They're telling me now early September, so maybe I'll have the car running in October, but I've missed the heat of the summer, so it will probably have to wait until next year before I can really give them the acid test. For what it's worth, when I broke the new cam in on the engine a few weeks ago the oil temp was up to 230 for at least 20 minutes, with the engine running at 2000-2500 RPM. This didn't affect the covers at all; they are still nice and clear.