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Been a great day for finishing projects as I wait to get my heads back.
I don't see this car needing a windshield washer so I decided to replace it with a vacuum reservoir for the brake booster.
I used this one from Summit, it fit perfectly where the washer bottle goes, attached with 2 five inch rubber lined hose clamps.
New 15/32 vacuum line from the hard line to a stainless T, out of the T to the reservoir check valve, the other outlet goes to a vacuum gauge in the cabin (not yet run when I took this pic).
Out of the reservoir straight to the booster.
I got 22 inches or so of vacuum on the system and it holds great and give you 3 or 4 solid brake applications before it drops to zero.

Still can't drive the damn thing but it should be a nice improvement.9C4F4CC5-96EA-4732-8D3E-F75C3F609E2428837DD5-9AF0-40BE-A258-4D57447E5170


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Last edited by jmardy
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J, you may already know this, but if you're doing wholesale brake changes to your car, you can entirely delete the shuttle valve under the brake booster. The moving shuttle inside the valve has no spring returns, and varnish tends to build up at the ends of the shuttle passages. Then if for any reason- including aggressive brake bleeding, the valve travels to the extreme end of its travel, it tends to stick there.

That essentially cuts off almost all fluid flow (and stopping power) from either front or rear brakes, depending on which direction the shuttle moved. Kind of a bear to diagnose if you're unfamiliar with Pantera brakes. It's also a messy job to move the shuttle back to its center position without removing the assembly from the front trunk. Its only function is to turn on a red warning light in the dash, ostensibly for low brake fluid warning, but two other things also turn on the same light, diluting its function.

Note also the stock (Ford?) plumbing for the stock non-adjustable proportioning valve limits brake pressure to the entirely adequate FRONT calipers while running full pressure to the toy-like rear calipers, for reasons that have always escaped me. If you install a manual proportioning valve for brake balancing, remove the stock one as they will fight each other.

My Philosophy on connections, whether they are electrical or tubing, is the less connectors gives the less probability of component failure. With that in mind……

A vacuum reservoir certainly makes sense for an engine proven to be incapable of supplying the necessary vacuum. But you have said you have not yet driven your car?

Perhaps you are building an engine that you are convinced will need a reservoir for correct brake operation?

without a little bit more information on your situation, I, like Simon, am still wondering why  


Larry, if I'm honest, I wanted to run a vacuum gauge and decided the easiest place to tap in was the feed to the booster. Since I was going to have to T something anyway, I figured why not add a reservoir.
Maybe I'm just bored and looking for things to do while I wait for my heads.
It won't be the first time I solved a problem I didn't have.

😎😎WHAT ‼️❓❓

are you saying you have a tendency to over-extend the scope of a project while  you are in the middle of it?

my good wrench turning buddy and I often pause in our tasks and our bench racing to look at each other and just go, “it’s a sickness, you do realize that, right?”

consider this an official welcome as a member in good standing of the “ well, I was in there already, so ….” DeTomaso family.


@jmardy posted:

Thanks Doug.
A lot of decisions on that engine build are perplexing, like those funky 5/16 to 7/16 rocker adapter things.

When you look back, you will realize that the whole thing is actually fun, including the interactions and maybe even the disagreements?

You are just caught up in the intensity of everything at the moment.

Take your time. Don't make hasty decisions is what I'd advise.

There is lots of experience here and a spirited bunch as well so don't be surprised if we start throwing spit balls at each other?

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