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oil coolers add complexity, cost, weight, and expense. To do it right is going to cost you, there's no way around it. For 3-4 track days a year, you're better off with a high capacity pan and a
synthetic oil.
There are a few good thermostats available. But even when closed they allow about 10% of the
oil to move through the cooler. When you're not on the track they will keep the oil too cold. On a cool morning it will be common to see oil temps aroun 120-140*F; that's too cold to work correctly.
Oil has a temp range where it does what it's supposed to do. Minimum temps seems to be about 160-180*. For the upper limit it's also a function of time. A few short bursts to 240-250* for a true
synthetic oil is nothing to worry about. BTW, there's only 4 true
synthetic oils on the market, and Mobile 1 isn't one of them.