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Is that a power brake unit or manual????

Is it mounted on an angle toward the engine??? (Forward most end toward the engine???)

Keith, I'm pretty sure it is an "Electro-boost". I.e., a electrically powered MC/booster combo where the booster can be mounted elsewhere.

Once Mat posts more pix and PNs we can scope it out.

My QUESTION is: will the MC provide enough line pressure with the Packard stock 1:1 pedal location?

Craig

I suppose the answer to the line pressure question is another question:
What is the diameter of the piston in the Master cylinder???
Does it have a long enuf stroke. Looks like it should have enuf stroke from the pic.

But if the piston is much over 11/16" diameter at the max it will create a hard pedal. That is unless the electro boost is so much more powerful than the vacuum boost.

If I'm reading pg 116 of the ABS catalog correctly, it does 1900psi but it also mentions adjustable from 1600 to 2500psi so we'll hope a lower input pressure could be covered. Any one have any idea what the standard BTV puts out. The only worrisome thing is how much reserve if the battery goes dead--of course, I speak from experience BTV's don't work well when engine dies either. What will be interesting is how a poster in another threads conversion with a dual diaphragm vacuum booster works out.

The guys at ABS advised that they had recently installed one in a 1956 Packard. I have attached a picture of the instruction for the unit which is a 10-59-6 model.

I can't comment yet on how well they will work as you can see from the images that I have no engine in the bay. I don't know too much about the technical side of the unit but any questions about the unit i'll pass onto my mechanic or it could be worthwhile chatting to ABS power brakes in CA

I will keep you all informed of any progress but until the re-spray & engine is reinstalled there wont be much to report on for a few weeks

Cheers,
Mat

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My experience with BTV is that there is 3hree pretty good brake applications allowed after the engine dies. This is due to the vacuum reserve can mounted under the left fender.

My Ford conversion gets about 3hree good brake applications too.

If you're not getting the power boost reserve without the engine running as PackardV8 describes, you've either got a faulty vacuum check valve or a leak in the system. The faulty check valve will not affect booster performance with the engine running, but a vacuum leak can.

Not sure if my comment about BTV and engine dying provoked these responses about reserve or not. The electroboost advertises up to 10 which is pretty good.

In our case, the reserve was there and working but problem happened when engine died due to vapor lock. We were going up a winding mountain highway. Let me tell you, when applying pedal until reserve is gone while going backward trying to steer toward a clear spot is not something I'd want to be around again. Thank goodness traffic was light, I wasn't driving and the person who was is quite large. He was literally standing on the brakes with a lot more force than I could have done. Aside from losing the power assist, going backwards down an incline -- thank goodness it wasn't horribly steep there -- really taxes the brakes and they do not want to stop a heavy car--slow it down slightly is about all. I'm of the belief the "self-energizing" feature of brake shoes is slim to none going backward.

Correct - no self-energizing feature in reverse, typical of all Bendix brake systems of that design regardless of car make. That was perhaps one advantage of the Chrysler (Lockheed) center-plane system with the two half-wheel cylinders, or of other brake systems where each shoe has a fixed anchor. Of course they lack the self-energizing feature when going forward.

Packard34
Mat,
I just installed the ABS electro boost system in my 56 400 and I absolutely love the system. The brakes work better than they ever have and the pedal feel is far superior to the BTV. The only drawback is the noise the electric pump makes, about the same as the leveler. It cycles when you use the brakes, more so in traffic, less on the open road. I'm planning on posting pictures and explanation of the installation soon.
Jed