to push more volume through
your master cylinder you would have to get one with a larger piston. This will firm up the peddle, give you less travel and significantly deteriorate your braking ability because you have lowered the fluid working pressure.
If you wanted less volume you would need one with a smaller piston which would give you a softer peddle, more travel and significantly MORE braking ability because you have raised the working pressure.
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy