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Mater/slave cylinder rebuild

If you don't want to read my above post...

Alright, Hydraulics 101. When you increase the size of a hydraulic piston, it now pushes more fluid with the same movement. Conversely, when you decrease the size of a piston, it moves less fluid with the same movement.

I'll give you two scenarios and you can vice versa them on your own. So, here's what happens when we change the master cylinder. Lets make the bore bigger. You'll be pushing the pedal the same amount as normal and because the bore is bigger, you'll be pushing more fluid. Since you're doing more work with the same movement, the work will be harder, i.e. the pedal will be stiffer. This translates into more clutch movement with the same pedal movement.

Now, lets make the slave cylinder bore smaller. With the same fluid movement coming from the master cylinder, the piston now moves more than it did before. Again, we have harder work with same travel so pedal is stiffer. Since the piston moves more, the cluch releases more for the same amount of fluid coming from the master cylinder.

Understand now? This applies to all hydraulic systems so if we discuss brake masters and caliper piston sizes, you'll be able to apply this to that as well.


Found the right one after three tries.
The smaller slave cyclinder is .75" or 3/4
can be found on the 1989 MITSUBISHI SIGMA V6 3.0 Liter FI

The bigger cyclinder measured .7904 but in the book it was 13/16" (.8125) can be found on the 1991 and 1992 galant vr4's

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