What exactly are valves and cylinders when talking about car engines? Say a car has 3 cylinders or 8 valves for example.
There are intake valves and exhaust valves. On the intake side, the intake valve opens which lets the fuel/air mixture into the combusion chamber. At some point (measured in degrees of crank rotation) the intake valve closes, the air/fuel mixture is compressed and ignited by the spark plug. Then the spent mixture exits the cylinder when the exhaust valve opens. Valve configuration varies somewhat, but regardless of how many valves there are there will always be at least one intake and one exhaust valve. Some cylinder heads have 2 intake and 2 exhaust valves which is what is described as the 4-valve per cylinder setup. Regarding Car Cylinders, the answerer says Cylinders in a car engine are pretty much like rowers in a boat. But they are not. Rowers always row in synch with each other. Cylinders are made to be out-of-sync for smoother operation. The more cylinders you have, the smoother the engine runs. Compare a 1-cylinder minibike with a 4-cylinder motorcycle (both air-cooled), or a 4-cylinder to an eight... big difference in smoothness.
