Lets talk about the oil cooler some more...
Sometime in the mid 80s, I added an oil cooler to my car, then still with a 2.6 engine. I finished the installation, with the (13 row MGB) oil cooler mounted to the X-bars in front of the radiator, still visible in the grill opening.
I threw some clothes in the car, and set out on the twelve (12) hour drive from Louisiana to Florida; I'm barely twenty (20) minutes into the drive, at 4:30 in the afternoon, and the temperature gauge is climbing! At about 220*, I park under an overpass and have a look-see.
Knowing the oil cooler was the only thing I had worked on, I figured it had to be the problem, so I unbolted it (leaving the fluid connections intact) and Ty-Wrapped it behind the shroud, completely out of the airstream. And then set out again, watching the temperature gauge drop and hold nearer the 180* mark. Voila, problem solved!
Turns out that mounting an un-ducted heat-exchanger in front of another heat-exchanger created a negative air space, and I wasn't getting any airflow through either one!
After my trip was concluded, I stuck the oil cooler back in the mounts I made, and starting out with a cold engine, and about twenty (<20) minutes later seeing the gauge climbing past its usual running point. Now firmly convinced, I set about cutting the duct into the front shroud!
My destination back in 1985? After spending a night at my parent's house in Spring Hill, it was on to Cypress Gardens to enter my car in a Tampa Bay Austin-Healey Club event held there! Though these pictures were taken in 2012, just prior to next time I would show my Healey in Florida, the trophies were won in 1985.
So the moral of the story, is where you put your oil cooler can also help or hurt your good intentions!