Register now to get rid of these ads!

Hydroboost brakes

Discussion in 'Off Topic Hot Rods & Customs' started by Roothawg, Jan 17, 2025 at 7:39 AM.

  1. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    Back in the summer, I was at an NSRA event and there was a guy with a really nice 55 Chevy. Pretty much a traditional build, but I was noticing extra lines on his firewall brake booster. He xplained that he had pulled a hydroboost system out of a Tahoe. He was raving about it. Said it was the best invest he had ever done. I haven't thought much about it, but recently I have had to do some research on power steering and it popped up again in one of my google searches.

    Has anyone done this swap? I would think other than the extra lines, the benefits would far outweigh the negatives. It takes up less space than a vacuum booster and a car with a healthy cam would benefit from it. A guy could fab up some nice hard lines and hide them in the frame, just having a flexible joint at the pump.

    Thoughts? Real life experience?
     
    Ned Ludd likes this.
  2. squirrel
    Joined: Sep 23, 2004
    Posts: 57,807

    squirrel
    ALLIANCE MEMBER

    I've been toying with the idea, too. I had an 06 tahoe with it, the brakes felt just a little different than vacuum brakes, but worked fine. Sure helps with clearance between booster and valve cover, which will be an issue on the Checker when I put in the V8.

    Let us see how it works out for you, when you get around to it...
     
    Roothawg and 41 GMC K-18 like this.
  3. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    My 56 F100 has the C4 Power rack. It's not finished yet, but I was researching the pressures for the Corvette rack vs other PS pumps to make sure everything is sort of matched up. I have sent an email to Turn One, which specializes in PS pumps. Oddly enough, they are in Saginaw, MI. Probably a bunch of retired GM/Ford Engineers.
     
    squirrel likes this.
  4. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    This is an expensive setup, but there are folks out there selling versions for half this price. However, this one is the most compact I have seen so far. wilwood.png
     
    bobss396, gnichols and Ned Ludd like this.
  5. squirrel
    Joined: Sep 23, 2004
    Posts: 57,807

    squirrel
    ALLIANCE MEMBER

    picture didn't come through? maybe post a link?
     
  6. TexasHardcore
    Joined: May 30, 2003
    Posts: 5,342

    TexasHardcore
    Member
    from Austin-ish

    I had planned to use a '04 Mustang Cobra hydroboost system on my '56 F-100. I was going to use the Cobra pedal assembly, master cylinder,. hydroboost unit, etc. I eventually decided to skip the hydroboost altogether and use '04 Mustang V6 pedal assembly, master cylinder, and vacuum booster. Not exactly sure what changed my mind on not using the hydroboost, but it was probably a few factors such as additional cost, additional failure points, etc. I also felt that if there was a booster or master cylinder failure, I could easily get replacement parts at nearly any parts store for a V6 over a Cobra.
     
    Last edited: Jan 17, 2025 at 8:42 AM
    Roothawg likes this.
  7. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

  8. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

  9. V8 Bob
    Joined: Feb 6, 2007
    Posts: 3,057

    V8 Bob
    ALLIANCE MEMBER

    Bendix introduced the Hydro-Boost in the early '70s (I think '73) to provide good braking assist in larger vehicles and light trucks because of the low engine vacuum levels resulting from strict new emission standards, along with the new diesel options. H B was popular until the engines were able to provide ample vacuum, then started showing up in newer cars because of tight packaging issues. I worked on and tested many vehicles with Hydro-Boost over the years with no problems, as they were very well designed and built, but I have no performance or problem knowledge of the non-Bendix aftermarket units presently on the market.
    Main advantages are slender size, and very good performance.
    Disadvantages are cost, and necessary power steering pump and plumbing.

    Bob
     
    Last edited: Jan 18, 2025 at 7:08 AM
  10. squirrel
    Joined: Sep 23, 2004
    Posts: 57,807

    squirrel
    ALLIANCE MEMBER

    rockauto sells new units for the Tahoe for about 3 bills....

    The plumbing fitting might get interesting, but I expect there is decent aftermarket support.

    Notice that the accumulator is located differently in Root's two links, one has it up top, the other down low (near the valve cover). Looks like they just flip it over to move the accumulator out of the way. (that's the round part that sticks forward, it stores hydraulic pressure while the engine is not running, so you have brakes when you first fire up the engine). Normal OEM installation has the plumbing fittings on top
     
    bchctybob and Roothawg like this.
  11. miker98038
    Joined: Jan 24, 2011
    Posts: 1,343

    miker98038
    ALLIANCE MEMBER

    I’ve got a hydroboost on my 55 bird, with 4 wheel disc. It’s been there close to 20 years, before they got popular. Originally a diesel Olds unit. Even with a shorter brake pedal arm it’s pretty sensitive. Reminds me of the old Plymouth’s from the early 60’s. There’s a Height’s pressure valve in the line to reduce boost too. Much lighter than my 05 Yukon.

    I did it for clearance problems (hood latch and battery). But it’s a lot of brake on a small car. Something heavier it would be better probably.
     
    Roothawg likes this.
  12. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    IMG_4652.png Here’s a basic schematic.
     
    bchctybob and porkshop like this.
  13. I've done a couple. I'm a believer. I have used Mustang parts which have become unobtanium because of low production numbers. Because there are several producers of brand new parts, other than the cost, I think they are better than vacuum boosters. At the risk of getting tarred and feathered, I want to mention that the elect. units from various new cars have been used very successfully. There is a company that adapts the late model mustang elect. power rack and pinion to a crown vic swap. If the goal is to always improve, it might be wise to consider some options that are current. If you're tired of power steering pumps and the occasional leaks with hydraulics, it is something to consider. 3 of my last 4 projects have been hydroboost. :)
     
    Roothawg likes this.
  14. oldolds
    Joined: Oct 18, 2010
    Posts: 3,491

    oldolds
    Member

    Chevy 1/2 ton vans and trucks used this in the 90's. Basically a trouble system.
     
    Roothawg likes this.
  15. squirrel
    Joined: Sep 23, 2004
    Posts: 57,807

    squirrel
    ALLIANCE MEMBER

    Chevy used them from the 70s to the 2000s....long time to be in use, some of them gave trouble, some worked a long time
     
    SS327 and Roothawg like this.
  16. Okie Pete
    Joined: Oct 29, 2008
    Posts: 5,564

    Okie Pete
    ALLIANCE MEMBER

    Diesel powered pickups use this system.
     
    Roothawg likes this.
  17. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    Ned Ludd, ekimneirbo and Okie Pete like this.
  18. rockable
    Joined: Dec 21, 2009
    Posts: 4,743

    rockable
    ALLIANCE MEMBER

    I have a friend who has built several rides with CPP hydroboost and won't use anything else.
     
    Roothawg likes this.
  19. ekimneirbo
    Joined: Apr 29, 2017
    Posts: 4,824

    ekimneirbo

    I'm putting some on my 99 S10 because of the valve cover clearance. Here is an old article on doing the change. On mine, which I've installed an LS3 in, I thought about the fact that the fluid reservoir was designed for Power Steering and was kinda small. I made a somewhat larger tank with 2 return lines because I felt larger capacity might be helpful. The old HAM shaped power steering pumps can be had with either 1 or 2 return lines. The newer pumps (as far as I know) only have one return. People "T" the return together. I didn't like that solution, so my tank has provisions for 2 returns. Just my personal choice....don't know if it helps or not.

    Hydroboost1 001.jpg
    Hydroboost2 001.jpg
    Hydroboost3 001.jpg

    Hydroboost4 001.jpg

    Hydroboost5 001.jpg
    Hydroboost6 001.jpg

    Hydroboost7 001.jpg
    Hydroboost8 001.jpg
    Hydroboost9 001.jpg

    And a little more helpful(?) info

    Perfect Power Steering 1 001.jpg

    Perfect Power Steering 2 001.jpg
    Perfect Power Steering 3 001.jpg
    Fittings Power Steering 1 001.jpg
    Fittings Power Steering 2 001.jpg

    Power Steering Adapter 1 001.jpg
    Pwr Steering Hoses 1 001.jpg Pwr Steering Hoses 2 001.jpg
    Pwr Steering Hoses 3 001.jpg
     
  20. Black_Sheep
    Joined: May 22, 2010
    Posts: 1,491

    Black_Sheep
    Member

    I’m currently waiting on a hydro-boost kit for my ‘69, the cam in the 440 doesn’t make enough vacuum to run a conventional power brake booster. I asked a lot of questions of owners who had a hydro-boost on their cars, everyone I spoke to was happy with the upgrade. The manufacturer says that I will have 2000 psi at the wheel using their system. The car has 11.75 front disc with 4 piston Wilwoods and stock 11” rear drums so it should stop really well. I guess I will find out…
     
    Roothawg, ekimneirbo and SS327 like this.
  21. My 04 half ton 2wd suburban has one. Not sure how the factory decided who got vacuum brakes and who got a hydroboost.

    Mine is leaking PS fluid like a sieve currently, and this thread reminded me. I have a new Delco unit but it's pretty cold out so I'll just keep refilling it.

    That might be a negative, that it could leak when worn out, but I'm sure your hot rod won't have 200k+ miles like my old Burb.
     
    Roothawg likes this.
  22. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    That's good to hear.
     
  23. DSC04951 (Small).JPG
    This was the 1st install on the white 51. The truck had a 4.6 2 valve but the engine bay got full. I used factory lines on that one. The next unit I did had aftermarket plumbing and was way neater. More expensive but looked like it belonged on a rod. DSC02649.JPG
     
    Dick Stevens and Roothawg like this.
  24. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

    I think it's the way to go. I will just have to wrap my mind around how everything gets plumbed, so I can use as many hard lines as possible.
     
  25. If you do a little research, you will see that some of the cobra kit guys have run hard lines down to short flex lines on the engine. I got lazy and didn't do that. They polish the lines and it does look good. :) Did I mention lazy? LOL.
     
  26. mustangsix
    Joined: Mar 7, 2005
    Posts: 1,451

    mustangsix
    Member

    These days it might be easier to use an electric booster-master combo from a Tesla, Nissan, or Honda, esp if you don't have a pump already.
    Several different configurations that will easily fit in the same space. Looks like just three or four wires to hook up.
     
  27. Roothawg
    Joined: Mar 14, 2001
    Posts: 25,437

    Roothawg
    Member

  28. mustangsix
    Joined: Mar 7, 2005
    Posts: 1,451

    mustangsix
    Member

    Yikes! The junkyard Honda version costs about a tenth of that one!
     
  29. Ned Ludd
    Joined: May 15, 2009
    Posts: 5,263

    Ned Ludd
    Member

    If like me you're prone to runaway research, the question arising out of making peace with an otherwise redundant power steering pump is, how about go full Citroën? Do everything hydraulically: power windows? air suspension compressor? heater fan? what else? Not one single electric motor in the entire car, because it's all hydraulic.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.