The Ford Barn

1948F-1Pickup · 02-18-2024, 05:49 PM

The movement increase is about 3/8" at the master when comparing the larger bore master of 1 1/16" and the greater amount of piston movement with the smaller bore master of 1 inch. (0.866" piston travel in the 1 1/16" bore to move 1 cubic inch of brake fluid vs 1.27" piston travel in the 1" bore to move 1 cubic inch of brake fluid)

With that extra 3/8" AND the pedal ratio, you might very well bottom the brake pedal into the floorboard on some vehicles/applications.
It wasn't a problem on my '48 truck but it just underscores that you wouldn't know the true story unless you did the math.

02-18-2024, 05:49 PM	#17
1948F-1Pickup Senior Member Join Date: Oct 2015 Location: Socal Posts: 845	Re: dual master cylinder The movement increase is about 3/8" at the master when comparing the larger bore master of 1 1/16" and the greater amount of piston movement with the smaller bore master of 1 inch. (0.866" piston travel in the 1 1/16" bore to move 1 cubic inch of brake fluid vs 1.27" piston travel in the 1" bore to move 1 cubic inch of brake fluid) With that extra 3/8" AND the pedal ratio, you might very well bottom the brake pedal into the floorboard on some vehicles/applications. It wasn't a problem on my '48 truck but it just underscores that you wouldn't know the true story unless you did the math.