Seems there are some disagreements regarding hydraulics and some
misinformation/misconceptions being bandied about so I thought a basic
hydraulics less on may be in order.
I'll keep the math simple in keeping with my simple nature .
A hydraulic cclinder ( in this case a master) with an area of 1 sq in
with an external force applied to it of 100 lbs will produce a line
pressure of 100psi. If you increase the area to 2 sq in the line
pressure will be 100/2 or 50 psi . 4 sq in would give you 25 psi ad
infinitum . If you increase the force on a 1 sq in cylinder to 200 lbs
the line pressure would be 200 psi . 100 lbs applied to a 1/2 sq in
cylinder would produce 200 psi .
Now we get to the other end, in this case the wheel cylinder or caliper
. If you apply 100 psi to a 1 sq in cylinder internally it would apply a
force of 100 lbs . Applied to a two sq inch cylinder it would apply 200
lbs force . The bigger cylinder applies more force .
Now there's the issue of travel . For a 1 sq inch wheel cylinder to
move 1 inch would require 1 cubic inch of fluid . A 2 sq in wheel
cylinder would require 2 cubic inch of fluid . For a one sq inch master
to supply 2 cubic inches of fluid would require 2 inches of travel .
That's where the force multiplication involved in hydraulics comes into
play, 100 lbs of force on a 1 sq in master moving 2 inches gives 200 lbs
of force on a 2 sq inch wheel cylinder moving one inch .
Hope that's clearer than mud .
Regards
John
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