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**1project2many** · 11-29-2014, 10:07 PM

Breaking down what Orrie G. said with a little more detail:

Drum brakes use return springs to pull the shoes away from the drum. So the wheel cylinders are "emptied" each time the brakes are released. To apply the brakes you must refill the cylinder quickly and take up all slack between shoe and drum. Use 1/4" brake line to get as much fluid to the w/cyl as possible in the least time.

Most disc brakes allow the pads to sit extremely close to the rotor or even contact it. There is much less (if any) return built in to pull the pads back. So the brakes are always ready to apply with a minimum amount of fluid. Even though the caliper holds more than the w/cyl, it takes less fluid to apply disc brakes. In this case you can run 3/16" line to the calipers. It would not hurt to use 1/4" line, but it adds to the amount of fluid needed to fill the system.

11-29-2014, 10:07 PM	#6
1project2many Senior Member Join Date: Mar 2012 Location: Lakes Region NH Posts: 3,217	Re: Hard brakelines '59 Breaking down what Orrie G. said with a little more detail: Drum brakes use return springs to pull the shoes away from the drum. So the wheel cylinders are "emptied" each time the brakes are released. To apply the brakes you must refill the cylinder quickly and take up all slack between shoe and drum. Use 1/4" brake line to get as much fluid to the w/cyl as possible in the least time. Most disc brakes allow the pads to sit extremely close to the rotor or even contact it. There is much less (if any) return built in to pull the pads back. So the brakes are always ready to apply with a minimum amount of fluid. Even though the caliper holds more than the w/cyl, it takes less fluid to apply disc brakes. In this case you can run 3/16" line to the calipers. It would not hurt to use 1/4" line, but it adds to the amount of fluid needed to fill the system. Last edited by 1project2many; 11-29-2014 at 10:13 PM.