65 Barracuda.....what does this booster do ?

[Blue62Val]

Hi guys.

I'm in the process of getting an old Barracuda, and had no idea what the odd looking black thing was on the inner guard.
After googling a bit, apparently it is something to do with boosting the brakes ??? I've never seen these before - what the heck do they do.....there's already a booster on the brakes.

Just thought someone might know a bit more.

Thanks,
Peter

 

[RustyRatRod]

It's a vacuum reservoir.

 

[Blue62Val]

It's a vacuum reservoir.

But doesn’t that just do what the booster behind the master cylinder already does ?

 

[RustyRatRod]

But doesn’t that just do what the booster behind the master cylinder already does ?

No. It's a "holding tank" for more vacuum. It allows the booster to be used multiple times if need be without running out of vacuum and losing power assist.

 

[Oldmanmopar]

Holding tank as RRR said. They were usually installed on Engines with a higher lift cam for vacuum storage.

 

[cudamark]

The later booster has the reservoir as part of the booster. Those early Bendix booster are built a bit different. Instead of a rubber diaphragm, it has a leather seal on a piston. Not the greatest design IMO. The Bendix booster needs that extra reservoir to operate safely. Personally, I'd remove that entire system and go with a '67-up manual brake setup unless it's going to be a factory stock trailer queen.

 

[Bewy]

It is a very good braking system, lasts forever. If the brakes are working ok, leave it alone....

 

[Blue62Val]

It is a very good braking system, lasts forever. If the brakes are working ok, leave it alone....

Thanks, apparently the brakes are fine.
I've never seen one of those tanks before.

 

[Bewy]

Nothing to do with higher lift cams. My Custom Royals had the same system, low compression export 361 engine. 1958-59 Plymouths sold here also used that system, 318 Poly engine with a 2 bbl carb.

 

[65 Cuda 340]

Here's a picture of my 65 Barracuda's engine from 1969. Factory power drum brake car. You can just see the black box on the inner fender on the right side of the picture.