I finally got around to adding an external oil cooler on the 440 Dart.
I heard many good things about the oil cooler from a mazda RX and thats the oil cooler I installed. This cooler is expensive new but I always feel you get what you pay for.
This is a welded tank cooler healthy flat tubes in cooler with a built in thermostat to bypass the cooler if the oil temperature is less 160F. The fittings are 18MM adapted to JIC 10 I used a doughnut adapter in front of the filter and 5/8" ID hose to JIC 10 fittings. Lines are about 16" long and are not compressed especially at 50 PSI.
I thought the setup would have very low restriction on the 440 oil system.
BUT the oil pressure was always 65 PSI when normally hot running now the pressure has dropped to 50 PSI under all conditions when the oil thermostat is open.
I am thinking there could be a pressure regulator in addition to the thermo bypass but also could be restriction in the system.
A 440 needs all the pressure it can get and I am concerned about the 50 PSI especially when I run it up past 5K.
Any ideas?