Does size matter?

I'm doing a disc brake conversion on my 47 Chevy Sedan Devilry And would like to know if I can use the original 1/4" brake line for the front disc brakes & reduce the line diameter to 3/16" at the hoses going to the discs at the wheels without losing effective pressure to the front brakes. Do I have to re-do the front brake plumbing to 3/16" for the entire system? I know the 1/4" line will need (or move) more volume of fluid, but will braking fluid pressure be effected?

 

As far as I know (in any fluid or hydraulics) when you go from larger dia. line to smaller dia. your pressure goes up and vice versa (smaller to larger pressure goes down). Don't know how much of a difference it would make in your case but I know those proportion valves are there for a reason...

 

You have to go with the 3/16" for front discs or you won't have enough pressure.

 

use the size you want, it won't make any difference

 

It's a closed system. The pressure will not change with a change in line ID.

The line size has nothing to do with the pressure in the system. Pressure is determined by the piston area and force exerted on the piston.

 

^^what he said...

 

I thought the line size didn't matter as long as I reduced the dia to 3/16" at the calipers. pressure is pressure, determend by cylinder bore the rest is just movement of fluid volume. Right?

 

the only dimension that really makes a difference is the suface area of the caliper piston / pistons. the more surface area, the more clamping force exerted on the rotor.