Brake Master Cylinder Upgrades?

[Baskinator]

My master cylinder just took a crap after less than 15,000 miles, and I'm wondering if there are any known upgrades for the master cylinder (that don't cost $400). It seems that the originals aren't the greatest to begin with, and it would be nice to have something that I know will be reliable.

I would absolutely love to swap in a hydroboost unit from an Astro van, but I don't know if I'll be able to get one. It would be awesome to eliminate the vacuum booster so it wouldn't change idle characteristics, plus the brakes would be so much better.

[eaglefreek]

I thought the same thing, until I drove my big Eagle with the solid front axle and Explorer 8.8 with rear discs with the stock master cylinder and booster. With 35" tires, it stopped better than my little Eagle. The master cylinder developed a leak and doing some searching of the net, I came up with the idea of using a master cylinder from a 80's Ford E150. I had to source some adapters for the brake lines. It didn't make any difference. Still stopped about the same. I think the problem with it not lasting is the junk rebuilds that companies are putting out nowadays. Hydroboost is on my list for my little Eagle one day. I also thought about trying to install a later XJ booster. They supposedly offer more assist, but I have no idea if one could work in an Eagle.

[carnuck]

If there are any junkyards in your area, Hydroboost is usually pretty cheap. I had a '79 Lincoln setup I was going to put in mine, but illness has kept me from doing anything since the beginning of this year.

[captspillane]

I'm pretty serious about using hydroboost because it will make room for a clutch master cylinder with intergrated resevoir like they used in YJ jeeps. Those are cheap and much easier to find then the oddball Eagle unit.

My Scout has it and its awesome. In my Scout they didn't modify the output shaft instead there is a big spacer block. I want to make my own angled spacer block for use in Eagles.

[carnuck]

I'm going to grind the standoff plate from an old Eagle booster (rusted through) to make my firewall adapter.

[BenM]

You could look for an older NOS cast iron master from a power disc-drum Hornet or Gremlin. You need to know the bore size you want. Stock is 0.940/0.940. I haven't had bad luck with the aluminum ones.

You could look for a double diaphragm booster that fits as well.

[Baskinator]

Yes, the hydroboost will be my next endeavor on the brakes. I was also thinking about taking an old Eagle booster bracket and modifying it to the hydroboost unit for mounting.

I did just install another reman mc since I need to use the car. It seems to be braking much better than before, so that's good.

[Nightpath]

Could a brake booster from a XJ be modified to work with the Eagle?

[carnuck]

Probably. Some XJs use the same Master Cyl as Eagles, but the firewall adapter on the booster is a different angle AFAIK.

Edit for clarification

[Nightpath]

I think for ease I'll just order a reman and be done with it.