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Discussion Starter #1
I am installing my 858 4bt in a 64 IHC that I am restoring. I will be adding power brakes and a duel hyd. brake system as used on 1967 and later veh. I have all the parts to install a vacuum booster including a nearly new vac pump for my 4bt. But I am wondering if a hydroboost would be a better choice. I have P/S pump and also adding P/S so that would just be a mater of pluming the booster to it. My truck does not use vacuum for heater or windsheid wipers so no need for it unless I use the Vac. booster. If you guys do recommend hydroboost what year/truck do I look for to get it from?
 

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First off, your subject says "Hydrovac vs Vacuum booster?" both of those work off of vacuum, the Hydrovac being typically a remote mounted vacuum booster found on older big trucks.

Now, to the real question, "Hydroboost" or vacuum booster. To me it's not really a question, the Hydroboost is the way to go if you already have a PS pump.

If you have drum brakes front and rear than you may be slightly hesitant to go with the Hydrobooster, as they tend to be touchy on small vehicles with drum drum brakes.

This is the place to go for Hydroboost info, questions, advice, and parts:
http://www.hydratechbraking.com/

I bought my first hydroboost setup from there, great to work with, excellent service, and very knowledgeable.

My second hydroboost setup I got from a junkyard, as I then knew more about them and what I needed.

You will need a master cylinder designed to work with your existing brake system, be it disc or drums or a combination, and with the right bore size. Search the junk yard for a dual circuit one from a truck with brakes like yours.

The Hydroboosters all look about the same form very early on and still today. However, they have made numerous changes inside and the new ones are more dependable and have a better feel to the pedal.
So, the hydrobooster to have is from the newest truck you can find.

The Ford an the GM versions of the booster are almost identical, the difference being the details and spacing of the MC mounting surface and holes, so if you use a GM master you need a GM booster.

My first system I used a rebuilt Ford unit, I had a problem with it and was driving by Hydratech in MI, with a few days notice he had a new one ready and did the swap for me as I watched. with such short notice he only had new GM units on the shelf, and was able to adapt it to my ford MC with a little machine work and have it ready when I got there. Hydratech no longer sells rebuilt units, only new ones.

Read up on the FAQ and the forums at http://www.hydratechbraking.com/

Grigg
 

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Discussion Starter #3
Grigg, Thanks for getting me squared away on the terminology. I,ll check out both those sites. I'm going front disc rear drum. Hope Hydroboost is not to much for a 1/2 ton.:D
 

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The sites are the same

You should be just fine with hydroboost and front disc rear drums.
Hydroboost would be the way to go for you, and eliminate the vacuum pump, as they suck ;)

Grigg
 

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Definitely go with hydroboost. I simply scavanged the hydroboost unit, lines, master cylinder, and proportioning valve from the panel van that I got my 4bt from. Then I put 76-86 3/4 ton Chevy front disk brakes on the front AND rear of my truck and now it stops better than my Honda! You will not be sorry that you did it.
 

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Discussion Starter #6
Thanks for the replies. I was thinking that the vacuum pump might be the weak link in the system. I remember a few problems with hydroboost in their early days, but doesn't seem like you hear about it much anymore.:beer: :dustin:
 
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