Honda 500cc V-twin engine converted to run on compressed air

This engine was originally purchased new and retrofitted by engineer Paul Trentham. He had been hired to take over by Terry Miller's partner when Terry gave up the air car project due to health problems. When the project was finally abandoned, Paul gave the engine to the University of Washington and they used it successfully in their nitrogen car. This project was undertaken by Abe Hertzberg and members of the U of W aerospace engineering faculty. Several scientific papers were published as a result of the university's experiments and the car was used quite a bit around campus. Finally I was given the engine and had time to clean it and take pictures before I had to pass it on to someone else since I was leaving the country indefinitely. For more information on the engine and how it was designed and built, see the introduction to my book Air Engines.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

#1: As-is from the university, before cleaning.

Shown from the back (exhaust end).

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

#2: As-is from the front (intake/throttle end).

Power output splined shaft w/ bearing, lower right/front.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

#3: As-is from the university.

Right valve-head (in front).

On left:

Throttle.

Intake/front end.

Output shaft on left.

On right:

Chain & sprocket valve-op.

Exhaust/back end.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

#4: After cleaning.

Front/shaft/intake/throttle end.

Shaft lower right.

Throttle handle upper right.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

5: Throttle assembly from front.

Intake hose remnants stuffed with rags to keep dirt out.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

6: Right side of engine.

Exhaust hoses removed & hose barbs stuffed with clean rags.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

7: Valve gear assemble from right.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

8: Throttle assembly from right.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

9: From back.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

10: Valve gear assembly from above back.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

11: From left side.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

12: Throttle assembly from left.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

13: Valve gear assembly from left.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

14: Valve gear assembly from left.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added

15: Left cylinder with valve head removed.

Gasket is intact.

Piston is at top of cylinder.

air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added
air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added air engine made from Honda V-twin 500cc 4-stroke engine with rotary valve added
Thanks to the rocket scientists at the U of W for making Paul Trentham's air engine available to me.