Joe, I'm using the same oil cooler and even with my turbo here in FL
it was adequate. Looks like your thermostat is open all the time?
When you remove it, you open the flow to go directly from  the IN
chamber into the OUT chamber without being forced to take the long
path through the core. If you are removing the thermostat you must
plug the bypass hole.
Reversing the in and out hoses does not seem to affect the performance.
Buly