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Stock Hydro-Vac Power Booster W/Discs

990 Views 2 Replies 2 Participants Last post by  CJS57
I can't bring myself to install my brand new 7 1/2" "special thin" vacuum power booster that I purchased last year. It still sticks out too far in my view. I am hot rodding my car with a 1962 "period correct" theme.
So.... Would an original 57 Hydrovac work ok with my 10.3" Malibu front disc brakes? Where does a stock Hydrovac get the hyd. pressure? From the stock power steering pump? What if your car was ordered with PB but not PS? Is there another Hydrovac unit that has the same general sort of look as the original, maybe a truck unit or? Appreciate any and all input!

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The HydraVac uses engine vacuum to provide pressure boost to the stock master cylinder much in the same way that modern brake boosters work. The only difference is the HydraVac is separated from the master cylinder whereas the modern master cylinders mount on the front of the booster.
I can see no reason why the HydraVac could not be used with disc brakes, except that the rear brakes if they are drums may need a pressure regulation valve fitted to the rear feed line to prevent lockup.
Good Luck with your search for the HydraVac unit, they were fitted to many cars and trucks from the early fifties through to the sixties.
Thanks Thumper!
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