# Air over hydraulic braking?



## Conelrad (May 23, 2009)

It seems to me it might be an easier fix in some instances for power braking. Regular master cylinder, a small Bendix or Midland converter, and some compressed air. Plus the converter can be mounted just about anywhere in the car.

If you lost the air, you still have regular braking as well.

Worked well in a lot of older vehicles, and you have something onboard for that leaky tire.

Numerous compressors are out there, mostly for the hot-rod air suspension crowd.

Just a thought, mainly aimed at older car conversions without a vacuum booster.

DG


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## Salty9 (Jul 13, 2009)

It has been suggested and rejected. See: http://www.diyelectriccar.com/forums/showthread.php?t=39568


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## Sunking (Aug 10, 2009)

anoopkumawat said:


> What the is the advantage/s of using oil over air in a hydraulic system?


Fail safe, no air pressure and brakes are locked.


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## steven4601 (Nov 11, 2010)

The automotive Bosch/VW/Audi pumps are vibration free and very quiet. No need to add danger of modifying your existing master cylinder hydraulic brake circuits.


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## iti_uk (Oct 24, 2011)

Conelrad said:


> It seems to me it might be an easier fix in some instances for power braking. Regular master cylinder, a small Bendix or Midland converter, and some compressed air. Plus the converter can be mounted just about anywhere in the car.
> 
> If you lost the air, you still have regular braking as well.
> 
> ...


Easier?

Original system
+ small Bendix or Midland converter
+ some compressed air (compressor or pressure tank?)

versus:

Original system
+ small vacuum pump for original brake servo

More reliable, lighter, more simple and no need to go messing with compressed air.

Chris


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## piotrsko (Dec 9, 2007)

and if you are really serious about boost braking, but have power steering: Hydroboost on most ford and chevy 3/4 ton vehicles.


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## Conelrad (May 23, 2009)

anoopkumawat said:


> I know that in a hydraulic system, oil is used rather than water because water can easily vaporised under extreme use. What the is the advantage/s of using oil over air in a hydraulic system?


The English is confusing you..."air over hydraulic" means a standard hydraulic braking system with an air pressure servo providing the boost (or 'power') braking.

It is not a choice of one over the other...

DG


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## Conelrad (May 23, 2009)

iti_uk said:


> Easier?
> 
> Original system
> + small Bendix or Midland converter
> ...


As I said, it would mainly be of interest in a car WITHOUT a vacuum booster system to begin with...a lot of vintage cars didn't have power assist brakes.

DG


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## iti_uk (Oct 24, 2011)

Conelrad said:


> As I said, it would mainly be of interest in a car WITHOUT a vacuum booster system to begin with...a lot of vintage cars didn't have power assist brakes.
> 
> DG


Ahh, I understand.

If it were my project, my first path of interest would be to source a brake master/booster system from another car and retro-fit it into the subject car, then go from there.

Chris


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