I will say,I have been racing round track for over 12yrs with a remote oil filter mounted on the firewall above the valve covers. Without a drain back valve and have had no issues. When I start the engine I fast idle @ 2000rpm for one minute. High oil temp on round track engine's or any engine for that matter is because of low oil flow. Most racers use too heavy oil which will increase there oil preasure but decreases the flow to the bearings. Suction side of oil pump is way to small and to far away from the pump. Dont fool yourself when taking oil temp, if you are not taking it at the bottom of the pan were the sending unit is fully submerged at all times you are getting the wrong temp reading. If you have 30 psi oil preasure at idle when your oil is 215deg use a liter oil you will get more flow and better cooling.