I installed an oil cooler with temperature and pressure gauges over the winter in anticipation of more track days this year. Everything worked great on my first couple of tests, but I'm now worried about it getting up to temp on cold mornings. I've seen plenty of discussion about maximum oil temperature but can't seem to find anything about minimum. What should I consider the coldest safe oil temperature before I start "beating" on it?
For context: My kit has a Setrab STD934 heat exchanger, Setrab oil filter spacer, Setrab oil filter thermostatic sandwich plate, and -12AN hoses. This got my total oil volume to about 10 quarts. My understanding of the thermostat in the sandwich plate is that it allows for the oil to bypass the exchanger when it's below 180°F; it doesn't force the oil to bypass, but rather to take the path of least resistance. It was a few weeks ago, but I finally had a chance to drive the car when it was a hair over 40°F outside. Luckily, there were no leaks but my oil temperature was much lower than I expected on the first drive. I did not have an oil temperature gauge before and was not sure what to expect.
I idled the car until my oil temp gauge moved from its resting position to the minimum mark at 140°F and the oil pressure dropped to just under 50psi; which took maybe 5 minutes. As soon as I took off, the temperature stayed at 140°F. After about 10 minutes of 35-60mph cruising the temperature did not move. I pulled over and felt the exchanger. The front face was a touch above ambient temperature, the back face was warm, and the hoses connecting the exchanger were somewhere in between. I then got on the highway and cruised at 75mph for another 10 minutes and the gauge didn't move until I exited and was waiting at a light, where it bumped up to maybe 145°F. I was a little bit more spirited when accelerating from stoplights (without beating on it) on the drive back to my house and it went right back to 140°F as soon as I got moving. It then went to 145°F after it idled in my garage before shutting off.
I'm sure that the really cold air did not help at all, and that 140°F is a lot better than anything below 100°F, but I'm not sure what I should consider a safe minimum operating temperature to be before I give it all of the beans. Our early and late season events in NE Ohio tend to be quite cold and it's not uncommon to see a high of 45°F. I'm worried that there might be a situation where we switch work groups and an Autocross quickly and it might not give my car much time to warm up, and I wouldn't want to beat on a cold engine. I'm debating on making a removable cover for the oil cooler heat exchangers for days like this.
As a disclaimer: I understand that I probably don't need an oil cooler for Autocross, even on warm days. I plan on attending more track days and a couple of Time Trial events.
For context: My kit has a Setrab STD934 heat exchanger, Setrab oil filter spacer, Setrab oil filter thermostatic sandwich plate, and -12AN hoses. This got my total oil volume to about 10 quarts. My understanding of the thermostat in the sandwich plate is that it allows for the oil to bypass the exchanger when it's below 180°F; it doesn't force the oil to bypass, but rather to take the path of least resistance. It was a few weeks ago, but I finally had a chance to drive the car when it was a hair over 40°F outside. Luckily, there were no leaks but my oil temperature was much lower than I expected on the first drive. I did not have an oil temperature gauge before and was not sure what to expect.
I idled the car until my oil temp gauge moved from its resting position to the minimum mark at 140°F and the oil pressure dropped to just under 50psi; which took maybe 5 minutes. As soon as I took off, the temperature stayed at 140°F. After about 10 minutes of 35-60mph cruising the temperature did not move. I pulled over and felt the exchanger. The front face was a touch above ambient temperature, the back face was warm, and the hoses connecting the exchanger were somewhere in between. I then got on the highway and cruised at 75mph for another 10 minutes and the gauge didn't move until I exited and was waiting at a light, where it bumped up to maybe 145°F. I was a little bit more spirited when accelerating from stoplights (without beating on it) on the drive back to my house and it went right back to 140°F as soon as I got moving. It then went to 145°F after it idled in my garage before shutting off.
I'm sure that the really cold air did not help at all, and that 140°F is a lot better than anything below 100°F, but I'm not sure what I should consider a safe minimum operating temperature to be before I give it all of the beans. Our early and late season events in NE Ohio tend to be quite cold and it's not uncommon to see a high of 45°F. I'm worried that there might be a situation where we switch work groups and an Autocross quickly and it might not give my car much time to warm up, and I wouldn't want to beat on a cold engine. I'm debating on making a removable cover for the oil cooler heat exchangers for days like this.
As a disclaimer: I understand that I probably don't need an oil cooler for Autocross, even on warm days. I plan on attending more track days and a couple of Time Trial events.
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