Brake Sizing

(Difference between revisions)

Revision as of 06:18, 10 January 2012

Master Cylinder Size

• Larger bore Master Cylinder reduces pedal travel, but increases the force you need to push with your leg

• Smaller bore Master cylinder reduces the force you need to push with your leg, but increases pedal travel

or put another way: The larger bore has a lower pressure output (so then you must press harder with your leg!)

You want a pedal that doesn't move too much, so larger bore is better... but at some point you get brakes that are so hard to push down on that I'd be afraid to loan it out... Just use a 13/16 master cylinder and it works out great.

So you either stop there or fit a small booster (B210/610) or medium size booster (620/B310). The booster won't make the brakes any more effective but make it easier to apply. But in most cases a light car like the 1200 needs no brake booster.

Story: I have a disconnected booster in my truck -- with a late-model large-bore Master Cylinder -- and it takes too much pedal effort to do a panic stop in my opinion to be comfortable. The previous owner disconnected it due to the twin sidedraft carburetors (the manifold doesn't have a vacuum tap to connect up the booster).