Hydraulic brake booster

[jaybee]

Hydroboost units are starting to become available from the aftermarket.  This sort of thing is way too specialized to be tooled from scratch for hobby cars I would think.  Does anyone know where the hardware originates, specifics of how it's plumbing is set up, and how you might get it from an "alternate source"?

[enjenjo]

It originates from Ford and GM cars and trucks starting in the 70's. Most diesel powered cars and trucks used a hydroboost, and many with gas engines did too.

Outside of the booster, the only other special part is the pump housing, and a standard one can be modified to use it with a hydroboost, it just needs two return lines instead of one.

Plumbing is pretty easy, pressure from the pump to the hydroboost, pressure from the hydroboost to the steering box, and two return lines to the pump, one from the hydroboost, and one from the steering box.

That's pretty much it, they use a standard power brake master cylinder.

[phat rat]

My 02 Silverdo 2500 HD has the hydraboost system. I really don't like it. The pump shaft broke and guess what, no brakes or power steering. Imagine what that could have been like if it had happened when I was pulling my 30' travel trailer downhill  through the Rockies.  I was lucky it happened right in my driveway.

[47-forvette]

My 02 Silverdo 2500 HD has the hydraboost system. I really don't like it. The pump shaft broke and guess what, no brakes or power steering. Imagine what that could have been like if it had happened when I was pulling my 30' travel trailer downhill  through the Rockies.  I was lucky it happened right in my driveway.

Do the systems that came on your truck have a reserve cannister?  I have a "Hydratech" brake assist on my 47, and it has a reserve canister that  that is supposed to be good for two to three brakings after loss of the power steering pump.   There web site is:
http://www.hydroboost.com/  

They have some links to some videos with a guy in a 70 doing panic stops.

[phat rat]

Nope when the shaft busted that was it.  Hoses go directly from the pump to the master. I was making a turn in my driveway when it went and right away it was armstrong steering.

[phat rat]

Corey, went out and looked at my set-up after looking at the web site you posted. Hoses go to a unit on the back side of the master. So maybe it's supposed to have a couple of brakings left in it if the pump fails I don't know. What I do know is that I was backing my travel trailer into the spot that I park it in and all of a sudden I had no power steering, got out to check belt and found it ok, check fluid it was ok, got back in the truck tried it again still nothing. Unhooked the trailer pulled forward and no brakes.

[jaybee]

Looks like there ought to be a lot of them out there with all the Diesel pickups and other apps over the last 20 years, should be possible to put something together for less than $450.00.  Could it be set up with a regular pump and a T in the return line?  The presence/absence of an accumulator might be worrisome as losing your power steering OR power brakes could keep you busy, losing both would be even worse.

[phat rat]

mines not a diesel it's an 8.1 (496") my sons 02 HD
6L also has the same set-up. I'm not sure but I think all the HD's, gas or diesel are set up that way

[enjenjo]

I've built several systems in rods, fairly foolproof. Teeing the line should work, although I usually just install another hose  fitting. there is an accumulator built into the booster, but it's only good for about one more brake application, and if you do much steering,not that.

[ram-rod]

my C30 horse truck has this system on it  but the motor is out of it
they must be a fairly reliable thing if they are used on the big stuff

[47-forvette]

I went to the hydraulic booster to gain more ground clearance over the *" double booster I originally installed.  One Saturday we were pulling into the garage with the trunk full of cases of wine and other libations, in preparation for our wedding reception, and the lip of the vacum booster caught on an edge of concrete.  It came apart and I was playing bumper cars with my tool chest and washing machine.   Love those emergency brakes!!  I tried the 7" double booster after that and I was not satisfied with the braking performance, so tried the hydraulic and am very pleased.

[jaybee]

I went to the hydraulic booster to gain more ground clearance over the *" double booster I originally installed.  One Saturday we were pulling into the garage with the trunk full of cases of wine and other libations, in preparation for our wedding reception, and the lip of the vacum booster caught on an edge of concrete.  It came apart and I was playing bumper cars with my tool chest and washing machine.   Love those emergency brakes!!  I tried the 7" double booster after that and I was not satisfied with the braking performance, so tried the hydraulic and am very pleased.

Room under the car seems like a huge advantage for this setup with floor mounted pedals.  Besides ground clearance it should clear up enough space to make exhaust routing and other things that compete for that same space.  Some of the Tri 5 Chevy boards are buzzing about this setup.  They're heavy enough to marginal with unboosted disk brakes (at least in this day and age when most of our subcompacts have power assist) but a vacuum booster sits very close to the valve covers.  A 7" booster is about the max that will fit.  Still the hydroboost seems to be pretty pricey.  No one is going to engineer something this complex from the ground up just for the rodding market, so th obvious question is "what's the original application"?

[enjenjo]

Just a few cars that it was used on,  any GM diesel car 76 to 85. Lincoln Marks and town cars, about 75 to mid 80's, maybe later. Also Ford and Mercury full size, but not all of them. Ans most GM and Ford heavy duty pickups from the mid 70's until today.