Converting '68 Power Booster from Drum/Drum to Disc/Drum Master Cyl

[chevy_mike]

Hi guys, my '68 has factory power brake booster and is currently the stock drum/drum master cylinder. Since the booster works fine and I am going to convert to front discs, what master cylinder can I use for this booster? I have been told the '71-'72 have a different booster rod depth so this master cylinder can't be use but is there something from another vehicle that works with the '68 booster?

Thanks!

[Bus Ted Knuckle]

I believe that the booster and rod will work fine with a disc brake master cylinder from 71 or 72, it should bolt right up to the booster. The rod would not work if you are going from manual to power...but you already have power, correct?

You will have to re-plumb the brake lines though. Buying a set of 71-72 brake lines is the best way to go there.

You will also have to fab up some brackets to hold the brake line where it attaches to the hoses for the wheels. I cut the brackets off of the back of the crossmember and tacked them on the front.

[chevy_mike]

Yep, I have the stock '68 power booster now.

Cool, I was hoping that was the case but someone told me the rod lenghts coming out of the boosters were different pre '70 and post '70.

Thanks for the tip on the lines. Most likely will bend my own lines, having done so many in the past.

[Longhorn Man]

I know when i tried putting a disk/drum booster on a drum /drum truck, it wouldn't work.
If you end up getting a booster, I strongly recomend getting a new one. A used one can blow the diaphram and cause some seriouse problems. I once lost an engine to this.

[chevy_mike]

I'm not trying to put any other booster on my truck, I already have the factory one which came on the truck and works fine.

I am looking for master cylinder info to use with MY booster.

[chevy_mike]

Okay, so I have one yes and one no. Not any closer to a correct answer.

Since I am not ready to pull my stock drum/drum MC off of the stock booster, does anyone have a picture of a '68 PB drum/drum MC, where the rod goes into the MC (i.e. the side that mounts to the booster)? I want to see if it is a deep or shallow style.

Thanks!!