Here is how I did my front oil cooler behind an S bumper.
While replacing the rockers I ran AN16 lines inside. These were secured with cushion (Adel) clamps to prevent rattling. The lines exit in front of the door hing post and then through the factory bump out on the vertical fender support. The lines enter the body above and behind the battery box.
then I mounted the oil cooler. This was the only picture I could find during the mock up. I welded brackets on each end and closed up the front pan box section on the lower corners of the cooler. The cooler is a Setrab unit. Its not very big but did not need to be with direct airflow. The edges were blocked off to direct airflow through the cooler.
then I built a duct for it modeled after the RSR unit but smaller for my cooler. The duct is just sheet metal bent in a brake. The sheet metal was riveted to the tub with sealer.
Here is the final install. You can see how the lines come off the passenger side and then curve into the cooler. The duct has cutouts for the fittings. The lines could be disconnected from inside the car and the cooler dropped out the bottom without removing the duct.
The bumper has a cutout to match the size of the cooler. This was the best way to keep a front bumper mounted cooler without the bulbous RS oil cooler box. I prefer the look of the S bumper. \
I shaped a section of grill material to match the contour of the bumper so that it would better blend. I think it came out rather nice.
The system was highly functional and averaged 200F oil temps even in the TX and OK summers. The car was sold and last I heard was in Idaho area.
I am building a 72 right now and it will most likely have a similar oil cooler setup. Well, at least the oil lines will be hidden.
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