Here you go, Piston area and force.

I'll say it again, it's PLAN, where;

P= Pressure (average) in the cylinder
L= Length of stroke
A= Area of the piston is square inches
N= Number of cylinders

How simple is this^^^^^^???

You have FOUR and only FOUR ways to make more power. Obviously you can put it on the hose or add a hair dryer or three, but this specifically addresses what you can do with your basic components.

If you want to make more power, you can change or modify any or all of the above four parameters.

If you can do simple algebra, you can easily SEE that increasing the area of the piston will make more power.

To sum it up, if you want to make more power you can increase the pressure (by any means such as higher compression ratio, power adders...whatever), or you can increase the length of the stroke, or you can increase the SIZE OF THE BORE or you can increase the number of cylinders.

That's IT. You can make everything the same and make the bore bigger and it will make more power.

Make the bore smaller, lose power.

Claiming a smaller bore will make more power is 100% buuuuuuuuuull squirt.