Combustion chamber pressure tap

An apparatus to obtain a source of gas under high pressure from an operating, piston type internal combustion engine comprising:

• an engine block,
• at least one cylinder containing a piston connected to said engine block, said piston having a crown at a first end and a skirt portion below said crown terminating at a second end of said piston,
• at least one cylinder head connected to said cylinder,
• a combustion chamber formed within said cylinder between said cylinder head and said crown of said piston,
• at least one exhaust port being downwardly spaced from said cylinder head and communicating with said combustion chamber through said cylinder,
• at least one fuel intake port communicating with said combustion chamber through said cylinder,
• at least one pressure tap orifice formed in said at least one cylinder communicating with said combustion chamber positioned immediately above said exhaust port between said cylinder head and said exhaust port, said pressure tap orifice being exposed to said high exhaust gas pressure when said crown of said piston moves past said orifice when said piston is substantially at the end of its power stroke, said high pressure gas being directed to pressure accumulation means just prior to expelling said high pressure exhaust gases through said at least one exhaust port.