Hydroboost brakes.. Thanks CaptainFab

[Captainfab]

I don't think the hydroboost needs a different proportioniong valve. The hydroboost doesn't change the balance between the front and rear brakes as opposed to vacuum assisted brakes. It is merely a different way of assisting the application of force to the master cylinder piston. I would just use the '73-'87 disc/drum prop valve.

Originally Posted by 66farmer

I would like to bring this thread back up again. My question is what proportioning valve should be used with a hydro booster. I'm using 78 front disk and rear drum setup.

[66farmer]

Captain
Because of the cam I have in the BB (comp 280) I think it would be wise for me to start out with the hydro system. I'm going to pick n pull to see what I can find what make and model is the best to get the hydro system from. I will need to get the steering pump and brackets to bolt to my 78 454 as well. I want this to be a clean install so I will need your booster bracket. What is your thoughts on mounting the booster upside down I want the lines on the bottom.
Thanks for your help

[chad64chevy]

you can mount it both ways! some people mount it with the lines on bottom cause of more room between the heads and the booster! its more up to what way you want to mount it! i'm adding a hydro boost to my truck but i still need the steering pump and hoses!

[Captainfab]

Yes, as Chad said, you can mount them upside down. Lots of guys do.

For the hydroboost unit, the Astro vans seem to be plentiful in the wrecking yards, and most of them had hydroboost. Then the next easiest to find would probably be the '73-'87 GM 1 tons, and/or diesel powered trucks and Suburbans. As for the pump and brackets, there again, typically 1 tons with a big block. If you can't find a hydroboost specific pump, don't worry. You can always install a tee in the returnline.

[Rooster's 67]

OK So for those that have converted from vacuum to hydro, did you find the hydro boost to be more sensitive to pedal input? I am wondering if mounting the hydro boost to a factory vac booster bracket would make the pedal less sensitive due to the 1:2 ratio.

[66farmer]

Rooster
That was my next question to ask hope we get a reply

[padresag]

http://www.google.ca/search?q=hydrob...=isch&tbo=u&so
ron

[66farmer]

Went to Pick N Pull today got a hydro booster and master cylinder and proportioning valve from a 93 AWD astro van for $40 not bad. Know the question can I use the master and proportioning valve with my 78 C10 disc/drum brake system.
Thanks for the help

[Captainfab]

I haven't tried that, but it seems like others have. I think that may have been what Bubba327 used on his truck. If you have the '78 master and prop valve, I would use those.

Originally Posted by 66farmer

Went to Pick N Pull today got a hydro booster and master cylinder and proportioning valve from a 93 AWD astro van for $40 not bad. Know the question can I use the master and proportioning valve with my 78 C10 disc/drum brake system.
Thanks for the help

[Captainfab]

Hey Reid, do you have any updated pics of the hydroboost on your '60?

[bubba327]

Update on my hydro boost changeover--
I installed a hydro boost from a Astro van back in October and all is great. Brakes are really responsive and stop fast on dry roads .
Problem is that on the ice they are too touchy and lock up pretty easily.

I found a pressure reducer for use in a GM power steering pump when using a Ford rack and pinion that reduces the pressure and flow rate.
http://www.summitracing.com/parts/BRG-899001/

Has anybody used a either the Borgeson or the March pressure reducers on a GM power steering pump with the stock 71-72 GM gearbox AND a hydroboost??
I would like to take some of the" touchiness" out and fine tune this hydro boost as it works really nicely...

[Captainfab]

I can see where that would be an issue on slick roads. The only thing I would be concerned about in restricting the flow to the hydroboost, is that it will also affect the steering. Just how much I don't know.

[wheel1968]

lookin for a hydroboost bracket thanks -T

[bubba327]

Originally Posted by Captainfab

I can see where that would be an issue on slick roads. The only thing I would be concerned about in restricting the flow to the hydroboost, is that it will also affect the steering. Just how much I don't know.

Well, the truck is a short box, and has 235 radial performance tires , And it turns very easily now. It could be a little stiffer and not be a problem.
The March unit comes with 1-5 shims that can reduce the pressure at around 100 psi per shim that you install.
So, would decreasing maybe 200-300 psi cause any damage or issues with either the steering gearbox or the hydro boost??
So I wonder if a Ford rack and pinion could be used with hydro-boost at the lower pressure???
Anybody ever tried this????

[Captainfab]

I don't see the lower pressure doing any damage to either the steering box or the hydroboost. What I was geting at is that your steering would have less 'power' to it. I'm definitely interested in hearing the results should you decide to give this a try. I think it might work for your issue if you have the time to play with it.

[GMR-PERFORMANCE]

Hey Captin. Long time.. I have been slammed with running my harley shop. However. Have a few items I swapped around. Going to run a hot rod hyd set up. So needed to get with you on an idea I have. Got the truck together for panels , all shimmed etc. Got the auto wire harness going in. and the new 407 SBC will be done in 4 weeks!!!! I can see the light at the end of the tunnel.

Old motor but truck is a 62 with ASTRO VAN hydro unit

[crakarjax]

Would hydro units off suburbans work? I think they look cleaner with the single reservoir.

[GMR-PERFORMANCE]

They are on the 2003 tahoe's as well.. They look the same as our sons is disc drum set up. To me it would be a killer swap from the salvage yard as you could grap the hyrdo boost and complete front system as well and bolt it on!! ( alt, ps, water pump serpentine system) would make for a clean low buck set up.

[Captainfab]

In my experience, all the hydroboost units are the same physical size, but the factory mounting plates/brackets vary. That is why I sell the hydroboost mounting plates. You just remove the factory mount, and install the new flat mount, and it bolts up to any of my booster brackets. If you are lucky enough to find a hydroboost off of an early Astro/Safari van, as GMR PERFORMANCE did, they are a direct bolt up to my booster brackets. Also you do not have to use the master cylinder that comes on a hydroboost unit. You can switch it for most any 2000 and earlier GM power type dual reservior master cylinder.

Originally Posted by crakarjax

Would hydro units off suburbans work? I think they look cleaner with the single reservoir.

[GMR-PERFORMANCE]

I did forget about that direct bolt on deal without the plate.. HUH well goes along with getting old I guess LOL

[padresag]

this is how some of the early one mounted. just bolted on. this was out of a mid 70's 3/4t suburban. has been in my truck 30 years

By rondavid at 2011-09-23
ron

[Slow Build]

I was wondering about P/S pumps for this set-up. I'm guessing you can use a pump with built in reservoir. Does the fluid drain down into that reservoir when the engines not running? The reason I ask is that the Astro I got my hydroboost from (and others) have the remote reservoir style pump with the reservoir mounted higher than the hydroboost unit. This really must not be an issue since it hasn't been brought up but I have been curious.

[GMR-PERFORMANCE]

I am running a stock pump you can see the custom line kit in my picture.

[Captainfab]

The vehicles that came from the factory with hydroboost, ran a pump that has 2 return line nipples. Some of these have integral reserviors, and some have remote reserviors. I don't think the hydroboost needs a remote reservior. I think it is more of convience within the chassis it is installed in.

You can use a standard power steering pump with a hydroboost. You will just need to use a 'T' fitting to connect your 2 return lines into 1, so you can connect to the pump.

[Captainfab]

Thanks for mentioning that Ron. I had forgot about our previous conversation regarding this. I have yet to find one of those myself.

Originally Posted by padresag

this is how some of the early one mounted. just bolted on. this was out of a mid 70's 3/4t suburban. has been in my truck 30 years

By rondavid at 2011-09-23
ron