Doug Schwochert Subaru EA81 Turbo Powered Scorpion 1 Modifications

(10th January 1998)

Left side view showing engine and drive layout

Letter from Doug to myself:

Adam,

Here are some pictures of my Scorpion 1 with the turbo Subaru motor.

I built a seperate oil tank that was mounted below the engine. It had 2 drains, one from each valve cover, another one to drain the block from behind the front crankshaft seal and one more draining the crank case through the cover that you remove to pull the wrist pins out of the pistons. The turbo also drained into the oil tank. I drilled into the oil pump suction side and ran a line into the bottom of the oil tank for the pickup tube. This is where i ran into problems. The pickup line needs to be at least 3/4 inch ID pipe or line. I used 1/2 inch line at first and had oil starvation problems. The hydralic lifters were running out of oil. Make the suction lines and passages as large as possible. The oil sump should be at least 2 gallons. There is no crankcase vent on the engine. It uses blow by gasses to push the oil out of the engine. The oil tank is vented.
No oil cooler was used.
Empty weight on the Scorpion was approx. 475lbs.
I custom made an exhaust system to mount the turbo to. (see pictures)
I used a carburettor. A fuel injection system with a computer system would work better. I later changed mine over to EFI.
I had no cooling problems with this engine. I used an oversize aluminum radiator from a Mazda RX7 rotary motor. Always oversize the radiator. The engines are running at full power and generate lots of heat.
The Scorpion drive system is very tough. The Subaru and the original Evinrude boat motor both make about the same HP.

Secondary drive system