In the market for a new master cylinder. Looks like the factory bore size for a disc brake 1970 a-body is 1". Most of the ones I see are larger than that by a small amount. Mancini has one that is 15/16", and that is the smallest I have run across.
Just guessing here so...
Smaller bore = higher and firmer pedal?
Larger bore = a softer pedal and more pedal travel?
