Hi All! I am doing some work on an old nova and there are three sizes of wheel cylinders for replacement. The ones fitted are 14mm but there are some others available at 17mm and 18.x mm. I was under the impression that if I fitted bigger cylinders it would reduce the pressure to rear and more at the front as it requires more displacement. But I have seen a website that states the opposite.

So my question: Does fitting bigger bore cylinders on rear increase or decrease rear brake efficiency according to pedal displacement? How will this effect overall brake performance on the car?

Thanks in advance.
Andy

I always thought smaller bores = higher pressures. That's the way it works on master cylinders.

Bigger slave cylinders increase the braking. Smaller master cylinders increase the braking.

adrian

As adrian says
Ray

Line pressure is created by the master cylinder. When changing the slave cylinders, the larger the diameter, the greater the area. Since the force exerted on the pads/shoes is pressure x area you get a greater breaking force to the rear.

your rear braking will increase but you'll get more pedal travel