Description
Here is my latest vacuum engine, model HP-3421 by my numbering system. Now, plenty of high performance vacuum engines have been uploaded to this site, but what sets mine apart? Well, I got rid of all empty space inside the engine, allowing for improved efficiency and power. At TDC, the piston is less than 1 plate away from the cylinder head. Any less space and the piston literally jackhammers the cylinder head off.
Most vacuum engines have 2 strokes: Intake and power, which are controlled by a valve. Valve opens, piston goes up, valve closes, piston goes down. These conventional engines use the valve to close off the vacuum before the piston is all the way up, wasting an opportunity to make more power. In my engine, the piston sits so high in the cylinder that it closes off the airflow from the vacuum at TDC, without intervention from the valve. Only once the piston closes off the vacuum does the valve close and allow the engine to draw in fresh air. At the same time, I kept the weight of the piston, crankshaft, and flywheel to a minimum for the most possible power.
For the best performance, be sure to lubricate the crankshaft and cylinder walls with plenty of silicone oil during assembly.