Question: I wanted to know why a shorter, wider cylinder in a car engine performs better than a taller, thinner cylinder of the same volume. I think it has something to do with power but I think there are other reasons as well.
The cylinder in a car
(internal combustion) engine
The idea of the cylinder is to transmit energy to the wheels
and the more often this can be done the better, Therefore a shorter stroke (movement up
and down) is better since that will give a "kick" to the drive shaft more often. This is the power
concept that you mentioned because more work can be done in a given time if the ignition of
the fuel can be performed at this faster rate.
To consider the actual area of the
cylinder:
Assuming a given pressure (P) in the cylinder and a cross sectional area A the
force (F) downwards after the ignition of the petrol-air mixture is:
Force (F) =
Pressure (P) x Cross sectional area (A)
Therefore for a given the pressure the force
downwards is greater for the shorter stubby cylinder.