Big bores made room for the big valves that could fill cylinders at high rpm, and so make more power. Short strokes reduced piston acceleration at any given speed, helping to make high rpm ...

Using pneumatic cylinders from the LEGO Technic ... are no fuel-air explosions involved, these pistons are also double-acting thanks to a valve mechanism that switches the pressurized side of ...

PVC air cannons are great, and everyone should build one of these at some point in their life, but what really makes this build exceptional is the valve. [Ben] created a piston valve for this ...

Piston rings are thin metal seals clipped into grooves around the top of an engine's pistons that form a barrier between the pistons and cylinder walls ... even broken. Bad valve seals are ...