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Filling the combustion chambers with compressed air
The combustion chambers are filled with compressed air from a pre-filled tank of compressed air that is itself constantly replenished with air from an air compressor. It is quite easy to calculate the time it will take to fill the combustion chambers with compressed air at 125 psi. The next time you drop into the service station to fill your tyres you can check it out for yourself. A R13 size tyre has a volume of approx 3.5 cu ft. and takes just 15secs - 20 secs to fill with air at a pressure of 30 psi. The volume of the combustion chambers in the RPJ is between 8cu ins and 9 cu ins. I cu ft is equal to 1728 cu ins. So 3.5 cu ft is equal to 6048 cu ins. So the time taken to fill one cubic inch volume of the tyre equals 20/6048 = 0.0033 secs, the time taken to fill the combustion chamber if it has a volume of 8 cu ins will be 8 x 0.0033 = 0.0265 secs. (Both combustion chambers fill simultaneously but in the time taken to fill one combustion chamber). In this example the combustion chambers should fill in something like 1/8th of a second. However one must take into account that the rate of flow is delended on the diameter of the delivery pipe, which in most air hoses is ).5 cms. Thus if we use a 1/2 in delivery pipe air should fill roughly 16 times faster or in 1/128 th. of a sec. This is more than good enough to enable the efficient working of the engine.
The filling of the combustion chambers to the desired pressure by an external tank is easily achieved and is founded on basic physical principles. Air entering a vessel under pressure acts equally on every surface; See Fig 1a. If there is a half inch pipe leading out of a tank with a pressure of 125 psi, it follows that the pressure in the pipe will be 25 psi (i.e 1/2 ² = 1/4 ) but this is enough to push air into the combustion chamber, air will continue to be forced into the combustion chamber until there is enough force within the combustion chamber to resist any more air coming in, i.e., when the pressure in the combustion chamber is equal to the pressure of the air entering the combustion chamber in this case 125 psi. If the tank from which the combustion chambers are being filled is kept upto the required pressure of 125 psi. The combustion chambers should fill almost instantly.

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