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I was wondering if I could use the hydro boost master cylinder off of the 1985 wonder bread van that I got my engine from to run the brake system on my 1973 4x4 1/2ton dodge truck? And also what do you use for lines to mate the two? Thanks
 

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You can use the hydroboost, and perhaps the MC, but chances are the MC is to large for your calipers/wheel cylinders. If the bore size is close to your old one then it's probably OK.

If you have disc and drums or disc and disc you will want a MC that was used on the same setup, as sometimes there are differences in the MC that cause problems if not used for the same type brakes.

If you have drums and drums then a hydrobooster is not recommended, as the brakes can be a little touchy.

Lines and adapters can be made/bought at NAPA, as well as a bunch of other places.

This site has lots of great information on Hydroboosters, and also has any parts and lines you would need. http://www.hydroboost.com/ and http://hydratechbraking.com/forums/

Grigg
 

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I was wondering if I could use the hydro boost master cylinder off of the 1985 wonder bread van that I got my engine from to run the brake system on my 1973 4x4 1/2ton dodge truck? And also what do you use for lines to mate the two? Thanks
I did on my truck and the brakes work wonderful! I used the hydroboost, master cylinder, proportioning valve, and the lines from the MC to the proportioning valve from my bread van, then just hooked my brake lines into the valve.
 

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Discussion Starter #4
So you used the everything from the van up to the valve and just hooked up the truck lines into the valve from the bread van and it works ok?
 

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If you don't understand what you are doing then the safest way to go is to use the MC and proportioning valve that is factory for your vehicle/brake system.
Then all you do is replace the vacuum booster with the hydrobooster.

What kind of brakes do you have on your project, and what kind of brakes did the "bread van" have?

If they are not the same chances are you can't interchange proportioning valves, and perhaps not master cylinders.

Grigg
 

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So you used the everything from the van up to the valve and just hooked up the truck lines into the valve from the bread van and it works ok?
Yes, exactly. I mounted the bread van proportioning valve down on the inside of the driver's side frame rail tweaking the factory bread van lines as I went, and then ran all of my hard lines on the truck to that. However, my brakes are not factory IH pieces. I have installed 3/4ton Chevy axles in my truck (D44 front, 14 bolt rear) and I have 1978 Chevy 3/4ton 4wd front calipers, rotors, and hoses in the front, and 1978 Chevy 3/4ton 4wd rotors and 2wd calipers and hoses in the rear. The truck stops incredible with four wheel disk brakes and will not lock the rear tires before the fronts, unless I am on a very icy road. With the hydroboost, fat tires, and four wheel disk brakes my truck stops better than my old beater 91 Accord! I think that the fact that the master cylinder was designed to work with a big wheel cylinder in the rear (1 ton) is what allows it to work as well as it does with my calipers in the rear. I am not sure though that it would be a good idea to run 1/2 ton brakes (especially in the rear) if you keep the MC from your bread van; I imagine the brakes would be very touchy that way.
 

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If the rear brakes end up too grabby, you can get an adjustable proportioning valve like this one from Summit.
 

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I have used that very valve on a 61 F350 I swapped axles in, had 14" disc brakes front and rear, with hydrobooster too.

Your brake system is not one you should be playing with if you don't understand what is going on, and are not confident in your workmanship. Mixing and matching parts can work if you understand why, but just guessing that it will work with no understanding is asking for trouble. I am sure you can learn by trial and error, but it may not be a good idea. :idea:

Grigg
 

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Discussion Starter #9
thanks guys for the help i am going to get some help for a local brake shop that does this type of stuff. it may be a little pricey but i would rather have it done right.
 

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thanks guys for the help i am going to get some help for a local brake shop that does this type of stuff. it may be a little pricey but i would rather have it done right.
Great plan!

Grigg
 

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thanks guys for the help i am going to get some help for a local brake shop that does this type of stuff. it may be a little pricey but i would rather have it done right.
What type of stuff does the brake shop do? Do they specialize in conversions, swaps, and transplanting brake system parts? If not, I can't see the benefit.

Don't get me wrong, if you are not comfortable doing brake work yourself then you should definitely have the work done by someone who knows what they are doing. But if you are taking it to someone else simply because they do 'this type of stuff', it seems like a big waste of money because you could also do this type of stuff. Do a little research and look at the bore size of your current master cylinder versus the one on the bread van. If it is a bunch bigger, then see if your current M/C will bolt onto the hydroboost and if not, do a little more research and find a M/C that will bolt on to the hydroboost that has the same size bore as your current M/C, providing that you are going to leave the original brakes in place.

Braking systems are not complicated, and if you are going to perform something as involved as a 4BT swap then you definitely have as much mechanical inclination as anyone working at the corner Midas shop.
 

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Braking systems are not complicated, and if you are going to perform something as involved as a 4BT swap then you definitely have as much mechanical inclination as anyone working at the corner Midas shop.
I agree. If you can swap an engine, I'm pretty sure you can figure out how to do the brakes.
 

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the Brake shop ain't gonna have a clue on anything but replacing parts on a bone stock braking system. its not rocket science, if your master cylinder is alot larger than stock, you'll likely have a hard pedal. if its alot smaller, you'll have a mushy pedal.
Dont see any reason why it should'nt work fine on a fullsize truck. I ran the stock hydroboost and master on several scouts and they worked fine.
 

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When you swap everything over, remove the pressure relief valve from the hydro-boost van's steering pump and swap it into your vans power steering pump. Then the systems power will be the same as it was, not different.

Also, brakes are not rocket science. They are a hydraulic system. So with a base knowledge of hydro systems, and the basic brake parts, this swap should be no big deal. First, you just have to know what every part does in the system, how to disassemble it, reassemble it, and what happens if it failed/has a problem. If you can do that, then you should be golden.

Goto your library and use that library card to pick up a few automotive braking manuals. I was supprised how much tech stuff our has when I went in last time.
 
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