This Zimmerman “Cirrus” 4-cycle V8 engine is a 1/6 scale model built by Profi M.E., 2001. Modifications to the original Zimmerman design are the addition of 4 cylinders and a geared flywheel instead of a propeller hub, making it suitable for a small automobile or power boat. The gear on the flywheel drives a water pump for circulating coolant around the cylinders, through the heads, and into the radiator. Each of the two carburetors fuels one bank of four cylinders.
The connecting rod journals on the crankshaft are located opposite each other at 180 degrees, while the pistons and cylinders are mounted 90 degrees apart. The internal parts are lubricated with a small amount of oil in the crankcase, and with oil mixed in the fuel. The external rockers require manual oiling before running the engine. The engine is 14”-long, 6”-wide, and 6”-high.