8th January 2004

The engine was started and run for just under two minutes. During this period the engine temperature would rise from room temperature to approximately 100 degrees Celsius at which point the engine was shut down. Data from the EIS were recorded.  This test run was conducted without anyone else present. Since the aeroplane is a pusher and I was located ahead of the aeroplane I felt very vulnerable. I cycled the power several times with a maximum manifold pressure of 25 inches of mercury.

Engine & Propeller RPM

The following chart indicates the rpm as a function of time. The RPM was intentionally cycled since this was the first test and there was no expectation of it's performance beyond those indicated by Don Bates model. Maximum RPM was achieved on the last cycle at 4200 RPM.

Manifold Absolute Pressure (MAP)

The MAP is indicated in the chart below. The engine is started seven seconds after the recording starts. The filters in the acquisition system slow the response time for the measurements. The first indication, from these tests, is that there is more horse power than I previously estimated. This impression was founded on the MAP measurement. Since the manifold pressure achieved only 5/6 of an atmosphere, and the engine was turning faster, by 100 RPM, than the Bates model had predicted even for the 64" diameter the indication is that there is more horse power to come.

When the propeller was constructed I had elected to extend the blade length a further 1.5", yielding a propeller diameter of 67", since I had a suspicion that the engine would produce more power than the Subaru data sheets suggested. My suspicion was founded on the fact that the exhaust system was tuned and less restrictive than the automobile from whence it was salvaged.