MAth question please

[LowBuckX]

I keep hearing that the rear piston should be 40 -60% smaller than the front piston. Is this correct?
So taking my 2.8" front piston 3.14x2.8= 8.792

So for 50% of 8.792 would obviously be 4.396 Then to find the Diameter of that would be 4.396/3.14= 1.4"
Correct so far? It dont seem right. 1.4 is 1/2 the dia. but in my mind that cant be 1/2 the area...

Help Im mathmaticly retarded.

[1970cuda]

Area is pi*r^2
Assuming 2.8” is diameter then 1.4 is radius
Area =3.14*1.4*1.4=6.1544 square inches
Half would be 6.1544/2=3.0772
New radius=square root of (area/pi)
3.0772/3.14=r^2
radius=.99 diameter= 2inches
i hope...lol

[6'9"Witha69]

Much better math.

[GetMore]

Yes, you need to do the area calculation, not circumference for this application.