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The turbo requires an oil drain to a low point on the engine with 0 back pressure. The oil pan is the perfect spot for this. Since my oil pan gasket was leaking anyway, it seemed like a perfectly reasonable thing to remove the oil pan and add the turbo oil drain. The picture above shows the bottom of the engine with the oil pan removed. Because an engine mount needs to be removed to get the pan off, the engine is supported at the transmission with a jack-stand. Also, the engine mount was replaced when the pan was reinstalled. The mount actually came apart in several pieces it was so badly worn.
As you can see, a 90 degree piece of pipe was welded onto the oil pan to allow connection to the turbo oil drain. It was later found out that enough clearance would have been available to simply weld in a straight piece of pipe. That would have made connecting hoses much easier.
A view of the oil drain inside the pan.
Here you see the bung installed on the oil cooler. The cooler was removed and sent to a rad shop who welded in the bung. This is to supply oil under pressure to the turbo. Oil could easily be tapped from the oil pressure sender at the drivers side of the engine, but I wanted to take oil from a spot doesn't take away from the engine. Since the oil cooler is before the pressure regulator, it is a perfect location. Later on, some fittings were installed to connect this bung to the oil hose.
The oil cooler reinstalled on the car. Notice the barbed fitting installed in the bung. This was later replaced with something better.
It was discovered that after trying to fit hose onto the oil nipple that there was not enough clearance between it and the radiator. So a 90 degree fitting was installed to point the barbed nipple in a more convenient location. Also shown in the picture is the high pressure fuel injection line used as oil hose. This will eventually be upgraded to stainless braided for both looks and long-term durability.
There are several more options for oil supply and drain covered in the Improvements, Changes and New Ideas section. It is highly recommend that you read through this information and examine your choices for oiling before you do any work on the project.