Brake Lines

[TexA]

I'm re-working the brakes on my 30 Model A. It was built by several (unknown) builders, so I have no idea who or where it was built, much less exactly what parts were used.

Anyway, I've moved the Master Cylinder inside, under the dash/cowl area. I removed the origional gas tank too.

So I had to re-do the lines to the MC.
In the process, I discovered the brake line to the front end (Mustang II) discs was done with 1/4" line forward to a T and off to each wheel with 1/4" line also.

The line to the rear end was made entirely with 3/16" line from the MC to a Proportioning Valve (variable) and on back to a rubber hose and a T and off to each wheel cylinder through a 3/16" line.

I've driven this car two summers and put quite a few miles on it and have always thought the brakes, although adequate, weren't quite as good as they should/could be. They always seemed a little soft but no amount of bleeding/adjusting could get them to feel "just right".

I was told I should change both fore and aft lines from the MC with 1/4" line to the T's on each end of the car and then use 3/16" lines to each wheel cylinder. That way I'd get more volume going to each end and higher pressure to each cylinder with the 3/16" line.

Any Comments? PLEASE........
Thanks
TexA

 

[jmlcolorado]

I'm re-working the brakes on my 30 Model A. It was built by several (unknown) builders, so I have no idea who or where it was built, much less exactly what parts were used.

Anyway, I've moved the Master Cylinder inside, under the dash/cowl area. I removed the origional gas tank too.

So I had to re-do the lines to the MC.
In the process, I discovered the brake line to the front end (Mustang II) discs was done with 1/4" line forward to a T and off to each wheel with 1/4" line also.

The line to the rear end was made entirely with 3/16" line from the MC to a Proportioning Valve (variable) and on back to a rubber hose and a T and off to each wheel cylinder through a 3/16" line.

I've driven this car two summers and put quite a few miles on it and have always thought the brakes, although adequate, weren't quite as good as they should/could be. They always seemed a little soft but no amount of bleeding/adjusting could get them to feel "just right".

I was told I should change both fore and aft lines from the MC with 1/4" line to the T's on each end of the car and then use 3/16" lines to each wheel cylinder. That way I'd get more volume going to each end and higher pressure to each cylinder with the 3/16" line.

Any Comments? PLEASE........
Thanks
TexA

I'm doing the brakes on my rat now. Im using a 68 C10 chassis that originally had 3/16" from the MC to a splitter up front that continued 3/16" to each disk. The rear had 1/4" from the MC to a prop valve ( non adjustable) then 1/4" to the rear above the axle to a rubber hose, then split to 3/16" to each drum.

I'd say your right to increase the size for more volume. If that size will stop a 68 c10, it'll stop an A.
Make sure the MC your using is setup for disk/drum though.

 

[TexA]

"Make sure the MC your using is setup for disk/drum though. "

THANKS for the reply jml, but how am I to know IF my present MC is OK for it's present use ?

I see there is one in a local retailers book for less than $40.00, maybe I should just get one and it may be OK. It has a 1-inch diameter plunger, or what-ever it's called......

THANKS
TexA

 

[ruggs]

I'm doing the brakes on my rat now. Im using a 68 C10 chassis that originally had 3/16" from the MC to a splitter up front that continued 3/16" to each disk. The rear had 1/4" from the MC to a prop valve ( non adjustable) then 1/4" to the rear above the axle to a rubber hose, then split to 3/16" to each drum.

I'd say your right to increase the size for more volume. If that size will stop a 68 c10, it'll stop an A.
Make sure the MC your using is setup for disk/drum though.

Your brake system must have been upgraded, Discs were not available in 1968 on a C-10.........ruggs

 

[offroadrolls]

Hydraulic brake info

http://www.peterverdone.com/archive/files/hydraulic system theory.pdf

 

[jmlcolorado]

Your brake system must have been upgraded, Discs were not available in 1968 on a C-10.........ruggs

Sorry, should have clarified. I have upgraded my fronts to disks from a 73. I bought a MC for Disk/Drum.

 

[jmlcolorado]

"Make sure the MC your using is setup for disk/drum though. "

THANKS for the reply jml, but how am I to know IF my present MC is OK for it's present use ?

I see there is one in a local retailers book for less than $40.00, maybe I should just get one and it may be OK. It has a 1-inch diameter plunger, or what-ever it's called......

THANKS
TexA

On a power master cylinder, there is a small indent for the ball from the booster to press on. A manual master cylinder has a deeper indent for the rod from the pedal.


I think your in good shape with a 1" bore.