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Hey guys,

My Bendix treadle vac is in pretty rough shape. The master cylinder is chipped around the reservoir, and there is part of a bolt stuck in it as well. I wanted to know if anyone has done an upgrade to a different master cylinder/power booster that fits. I've seen that kanters has a kit to overhaul your brakes with a modern master cylinder. Where can I get a master cylinder that fits and is ready to go for my '52 200 deluxe touring sedan?

There is no modern system that will just drop in due to the confined location and existing pedal ratio. Several have used the Universal Bendix type booster and dual master setup from MasterPowerBrakesmpbrakes.com/ or ABSabspowerbrake.com/ in one of several ways:

There is one setup that will fit the space but needs modifications to the pedal. It's the simplest and several have made that change. Downside is the pedal no longer looks stock or is in quite the same location. Check it out at Craigs Panther site under special projects.1956packardpanther.com/Panther/PantherProject_Index.html

There is another setup needing complete new brackets where the system is mounted higher up on the firewall above the steering column -- more like modern cars. It's got some pictures and a writeup on site.packardinfo.com/xoops/html/modules/newbb ... orum=3&post_id=29766#forumpost29766

There is another using a Ford setup but that needs a new pedal also and the unit is mounted in the Left vent opening. Info & pictures also in the thread above.

There are other setups using the ABS Electroboost or a master and vacuum remote power cylinder like the old Hydrovacs. Other versions of the Universal Bendix setup are being tried but no reports yet on that or on the completed Electroboost or Hydrovac installs.

Thanks HH56,
This is going to be the toughest part of this project. I'm slowly running out of money and ideas. I definitely want to go the safest route possible. All while spending the least amount of money. Craig's conversion seems to be the easiest. And i'm not all that worried about keeping it "stock" in appearance. That's probably the way I will go; but I plan on Keeping all four drums.

See post #31

packardinfo.com/xoops/html/modules/newbb ... rum=12&post_id=27924#forumpost27924

It's a 56 application, someone else will have to comment as to how close it is the same as your model.

Nice features of the F explorer conversion is all parts are available over the counter. Pedals availale at junk yards, minor cutt and weld on pedal. Very ez to make adapter plates to fire wall. Cheap and ez. readilay available parts.

Here's walkerman's 53 conversionpackardinfo.com/xoops/html/modules/newbb ... ic.php?post_id=67023#forumpost67023 Aside from the pedal shape, 52-6 are pretty much the same install space and all have the pedal ratio constraints. There will be slight plumbing differences on the S8's due to the brake light switch different mounting.

Guys,

After reading the posts on the forum about master cylinder failures. I have real concerns about driving my 53 Cavalier with the original braking system. (I have completely gone through and rebuilt the brake system.) Has anyone been able to adapt a dual master cylinder to the original Bendix treadle vac? I have looked through the posts and other sites and haven't seen anything. My car stops fine for the way I drive it. I would just like to have the added safety of the dual master cylinder just in case of a wheel cylinder, brake line or MC failure.

Thanks,
Dennis

The problem with adapting any modern MC to the treadlevac (or BTV) arrangement is twofold.

First is the pedal ratio. Almost all modern MC's require a 3 or 4 or greater to one ratio. At 1:1, the BTV ratio is simply not enough for any conventional cylinder. The BTV is able to get away with it because it's fluid is displaced via a relatively narrow hydraulic plunger being forced into a body of fluid over a long distance compared to fluid being pushed ahead of a larger piston for a short distance in a conventional cylinder.

The second problem but one more easily overcome would be the BTV utilizes the hydraulic section to both provide the vacuum seal at the end of the canister or shell and also uses the hydraulic plunger rod as the primary guide and support to the power piston.

Thanks Howard.

I guess my next project is going to be updating to a new brake booster and dual master cylinder. I was hoping there was an easier way.