Are you referring to an oil cooler for a Mazda RX-7 wankle rotory turbo engine? If so that’s different animal than an old school 4-Stroke 440 Chrysler engine. Is 160(F) the stock oil temp setting by Mazda engineers? That’s interesting if it is.

Really, motor oil operating temperature is best optimized at around 212 degrees (F) for a typical water cooled 4-Stroke engine. This will actually free up a few extra ponies versus 160 (F). The design oil temperature for modern water cooled engines is actually 212(F). It’s also why the pros want HOT oil when dyno testing; thinner, more flow, more horsepower, etc.

Unless one regularly sees oil temperatures over 212(F) such as racing and or turbo applications, it’s probably more detrimental than beneficial to utilize an oil cooler. This is where paying close attention to an accurate oil temperature gauge pays off. The gauge could be telling you that you need an oil cooler, or it could be telling you that you don’t need an oil cooler.

What’s your oil temperature gauge actually telling you?