So!! I took the current iteration of my inline 4 banger on a trip last week. 250 miles each way and no major problems. It ran a little hot on long grades in the heat of the day, (temps approaching 100 degrees) but otherwise performed well.
I'm figuring an oil cooler will fix the problem. I've installed them on trucks that had issues while towing big loads and the resulting drop in coolant temps were as much as thirty percent. One truck in particular went from running 240 to a cool 160. We had to install a 205 degree thermostat to get temps back into operating range.
I'm not towing and it only runs hot at high speeds. I'm thinking that the airflow to the radiator, it's in the trunk under a louvered trunk lid, is being diminished from the aerodynamics under the car at speed. The oil cooler will be placed in the wind stream at the front of the car where it'll work best when the car is at speed.
Anyway!! You should see the looks when I go around some fancy late model with a V8 or V6 engine driving that little 4 banger out in the open and squalling through the header!!
