How I got Hydroboost for under $80 (including lines)

[OneOffStroker]

Here's a thread that will hopefully save you guys some time & money while updating your trucks to better, safer brakes.

I got a Hydroboost with Master Cylinder & prop valve from a '94 Astro out of my local pick-n-pull for just under $30. When scavenging a hydroboost (HB) from Astro vans, look for the earlier 90's, as the later ones are mounted at an extreme angle that just might not work in our trucks. The earlier ones are mostly straight. It unbolts from the inside, near the brake pedal, and is overall easy enough to remove. I cut the stock lines at the gear box and the pump, just so that I could gauge how long they were, because that was the highlight of the savings.

Most HB swaps that I researched before I did mine used Earl's Pro-flex hose and fittings, which are pricey. Add to that the necessary adapters to fit up to the HB, pump, and gear, and these guys were in over $200 in just lines and fittings. Personally, I don't spend $200+ on 4 feet of hose.

Like I mentioned earlier, I cut the stock Astro lines to gauge how long they were. They were much too short, and would not work at all. BUT...the General made more than one truck with HB. The newer HD pickups had HB setups as well. They also had front mounted steering pumps and gearboxes, much like our trucks. I gambled and ordered a set of lines for a 2003 Silverado 1500 HD. They are very reasonable from RockAuto, but I spent a few bucks more and got the exact same parts (Edelman 92084 & 92095) from Summit, because their return policy is super easy, just in case.

Well, the lines were a perfect fit, except for the line from the HB to the stock gear box. The HB had a 18x1.5mm o-ring fitting, and the stocker uses a 7/16 Inverted Flare. I searched the interwebs and asked hydraulics shops for an adapter or series of adapters, but struck out everywhere. I thought I was going to have to return the lines and start over, but then I noticed something. (Actually I noticed it days earlier, but wanted to sound dramatic ) Even thought the new line had a metric fitting, it was a standard 3/8" line, as is the stock one. See where I'm going with this?

I cut off just the flared end from both lines, took the 7/16 flare from the stock line, put it on the new line, and put a double 45* flare on it. Perfect fit! While I was at it, I bent up a small piece of 3/8" tube I had and added the nut from the stock return line. This will allow me to run the return line into the necessary 'T' fitting without any drama.

So add up the cash...less than $30 for HB and M/C, and about $50 for lines, and that's the $80 Hydroboost.

[OneOffStroker]

Oh...I guess I should cover the other stuff...

I mounted it without any adapter plates or other stuff. You can buy adapters, or you can hack some stuff. I like to hack.
It went pretty easy, actually. The stock studs come out easy enough, so I knocked them out and started with a flat plate. I marked where the lower 2 studs come out of the firewall from the stock brake pedal assembly. I drilled them in the proper places, enlarged the M/C hole slightly, and the HB slid right in. The upper bolts in the firewall were just over top of the HB bracket, and the lower HB bracket holes were also in a good place. So good, in fact, that the vertical bolt for the steering wheel mount lined up perfectly. (Keep in mind though...I remade my firewall, so fitment might be slightly off from stock, but maybe 1/4" tops.)

On the inside, I cut the large end off of the HB actuator rod, just where it starts to transition. Then I unthreaded the stock clevis from the stock rod, and it slipped right over the HB rod. Once I get it all powered up, I'll set it where it needs to be and weld them together to take out any slack. (again, I shortened the setup because I moved the whole firewall in almost 2 inches, so in a stock setup, the HB rod probably won't reach the stock clevis. You'll have to be creative here on your own.)

[OneOffStroker]

And some finished shots:

Sexy, eh?

[OneOffStroker]

Ooh, I guess I should mention one last thing. Obviously, I have an LSx swap, and as such, have a newer power steering pump with the correct metric outlet port. If you have the original one and want HB, there are a few options that I can think of.

1) Replace your pump with a newer pump
2) Rob the outlet and it's inner piece from a junkyard pump (make sure you get both pieces)
3) if you don't want to do either of those, you can cut off the metric end of the new hose and the end of the stock hose, and reflare the new hose with the old fitting to mount to your stock pump, like you would for the gearbox.

[claytonisbob]

Dude, this is awesome. I'm totally going to go hit up the local pick n pull soon.

This would probably get more reads/comments if it were in the suspension forum imo.

[mknittle]

great thread I did the same on my 42 willys jeep. I am amazed at how it stops now.

[chris mc bride]

Man when i finsih striping the astro van ther will be nothing left to scrap. Already stealing the rear AC.The new trans it has in it.The rear seat(possibly). Now the hydro boost is on list.

[lowrollin70gmc]

I've grabbed all my hydroboosts from Astro vans due to the ease of adapting an already flat plate. If I may add a few more budget themed tips:


If you're doing a power steering swap while you're there pick up an 80s GM truck power steering box from the junkyard and it'll have the metric fittings already there and bolt up to the stock frame and pitman arm. Easy way to tell is to take off the supply (easy) and check if it's o-ring or flare. Grab at least the box side of the rag joint to make installation easier as the general changed spline count and size on some trucks. Shouldn't add anything to the cost of the pump.

You can also swap on the reservoir from saginaw pump to saginaw pump to get two return fitting on the rear of the pump (from a hydroboost vehicle such as a 80s truck with hydroboost. Or plumb both returns into a 3/8" T making sure the brake return runs straight through it.


Reservoir ---------------- T -------------- Hydroboost
-----------------------|
-----------------------|
-----------------------|
--------------------Box Return

[Cumminpwr11]

Thanks for this write up. I want to do this but wasn't sure where to start with my truck sitting on a 90 dodge 1 ton frame. Time to start looking for a hydrobooster and some lines!

Thanks

Chris

[jjzepplin]

Would this work on a 4x4 with one ton axles?

[jlsanborn]

Originally Posted by jjzepplin

Would this work on a 4x4 with one ton axles?

My K30 came factory with hydro boost. I'd say look for that booster/master setup in the bone yard.

[ABHaulR]

I got mine off an 73/74 one ton dually. All the lines worked great. I put this setup in my 83 cj7, after the completion you step on the brakes and it will bounce you off the windshield. Going to put the next setup on my 72 sub.

Dwayne

[72gmcshorty]

what is the benefit of hydro boost versus original brake booster (72 style)

[jlsanborn]

One advantage is that you're not relying on vacuum for brake boost. If you've got an aggressive cam that inhibits vacuum this is a plus. The other advantage is that its more compact than a big-o vacuum booster. Lots of guys squeal because it's a pain to get that valve cover off with the big-a$$ can in the way. The downside is that they're pretty touchy! I haven't experienced them in my C10 yet but even on the 1 ton when you're rolling forward, pressing on the brake while you crank the motor... when that sucker fires its like WHAM! Brakes on! I'd bet the autocrosser dudes wouldn't like them because of the loss of feel and resolution but the advantage (power) is there.

[ABHaulR]

Because of the size of tire and the weight of the Burb, That is why i went that route. I ran the stock for a long time with no worries, but with the added weight of towing it just the added security. Plus if your engine dies, you still have 2 or 3 pushes on the pedal to stop.

Dwayne

[bugmasta]

Tagged for later, thanks for the info
Posted via Mobile Device

[RustyHunk-O-JunkGuy]

Thanks guys, Good to know. I have a 67 that is getting a Cummins 12 valve and Allison swap. The info should help make it much cheaper.

[rcrahn]

Originally Posted by 72gmcshorty

what is the benefit of hydro boost versus original brake booster (72 style)

Pressure - the benefit is a dramatic increase in line pressure. A dual diaphram booster will produce around 700-800 psi of pressure in your brake lines. With a hydroboost it jumps to around 1500 psi.

If you are running 4 wheel disk brakes this matters. My son and I installed a hydroboost system on our 1969 Firebird. Purchased it through hydratech brakes in MI. It was expensive but being our 1st time we had excellent support. They are great people that make a quality product.

They also have some excellent technical info and videos on their website.

http://www.hydratechbraking.com/

Now - from personal experience....We found the inital setup to be very touchy.
We had all new components in our brake system. The setting of the clevis to the brake pedal and rod into the MC IS CRITICAL. As little as 1/2 turn can be the difference between preloading with brakes dragging and free wheeling. As me how I know. Damm thing held back a newly built Pontiac 462 no problem.

Couple other tips
1. We were advised to use Valvoline Synpower brake fluid.
2. The power steering pump needs to in top shape, not tired and leaking.

[Possmguts]

Originally Posted by OneOffStroker

And some finished shots:

Sexy, eh?

Isnt that upside down? The lines should be on the bottom... right?

[OneOffStroker]

Nope. It's installed correctly. But it's a fluid pressure system, so it could care less what position is up.

[suville]

I like, savin this, Thanks

[jjzepplin]

Good point about the power steering fitting. I just upgraded to a serpentine system and needed a flare fitting to use the older hose. I almost threw away the newer o ring fitting but I guess I should be keeping it in case I upgrade to hydro boost brakes.

[hugger6933]

I would like to add something here if I might about the pumps and the newer lines. You can screw out the big nut on the back of your pump[the older one]this is where the pressure regulator is housed by the way, and put one in from the newer truck say 82 up [to be safe I don't recall for sure what year they went to the metric design]and screw the newer nut into the older pump and that will solve the line problem. this may save someone from changing their whole pump out. I've also found when doing the hydroboost thing that adding the return line to the pump a Y fitting makes things happier than a T but there is not that much difference. Jim

[205harleyman]

subscribed

[72blazer_mud_bogger]

Bump and thanks for the great info