Brake Lines with Drum-Disc Swap

[AeroMoto]

Planning on doing the drum-disc front swap on my 73. Found a full 78 Dana 30 axle. So my question revolves around brake lines. I've got what I assume to be stock 73 dual bore master cylinder (non-power). Most places I've read that it's a good idea to go with a bigger master cylinder and proportioning valve. So my question is this:

For those that have done this swap, did you replace all the brake lines? I have 2 hard brake lines straight from my master cylinder: one to the front that T's, and a second to the back that T's. If I was to do a different master cylinder and proportioning valve I'd have to basically run new brake lines from the master down to the PV, then from the PV to the T's, correct?

 

[Jimbos76cj]

Planning on doing the drum-disc front swap on my 73. Found a full 78 Dana 30 axle. So my question revolves around brake lines. I've got what I assume to be stock 73 dual bore master cylinder (non-power). Most places I've read that it's a good idea to go with a bigger master cylinder and proportioning valve. So my question is this:

For those that have done this swap, did you replace all the brake lines? I have 2 hard brake lines straight from my master cylinder: one to the front that T's, and a second to the back that T's. If I was to do a different master cylinder and proportioning valve I'd have to basically run new brake lines from the master down to the PV, then from the PV to the T's, correct?

Can you post a pic of the T I've seen a few with the t when using front and rear drum. With using discs you want to remove the t. One port from your master will go the PV then out to the front wheels. Should be 2 lines going to the front. Then the other port will go to the other port on the PV then one line out to the rear.

 

[73CJ]

I just replaced the rubber lines to the original steel line when I put 77 disks on my 73. The drum master cylinder made me wonder why I was doing this swap. Then I put the disk non-power master cylinder from 78 CJ. Wow then I could stop after going through some mud and down a steep hill.

I left the proportioning valve on.

Since I have gone 4 wheel disks with D44s now I put a adjustable valve on the back brakes. It's fun dialing it in - go 10mph and nail the brakes. Repeat until the back are not locking up quite as much as the front.

Why did I wait so long to go 4 wheel disks?

 

[AeroMoto]

Thanks both of you. I'll post a pic of the T when I get home. I've been debating whether to spend thre extra money for a new master cylinder, proportioning valve and brake lines. Sounds like its worth the money. Do it right the first time and cry once, right?

 

[AeroMoto]

It's on the frame rail, front is to the left.

 

[AeroMoto]

73CJ, where did you find the brake lines? I'm trying to source mine now and am having trouble finding the right ones.

 

[Jimbos76cj]

It's on the frame rail, front is to the left.

Thats normal. Normally the rear brake lines T at the axle. If I remeber correctly the PV for Cj's have 2 front out puts and one rear. I guess it depends on the PV you get.

 

[Reddrig]

I just did a front and rear drum to disc. I used the original hard lines from the old MC to both T's front and rear. I replaced the hard lines from the T's to to all four wheels. Bought the prop valve kit which made the install easier from new MC and to the old hard lines which were in the original location under the hood..