stokerg

I have a 57 Olds Super 88 2 dr hdtp. I' like to upgrade the braking system and I like the concept of using the power steering pump hydraulic pressure versus a vacuum booster. It takes up less room and seems to be a more reliable system. Has anyone out there made this modification? Can I use the existing power steering pump or should I go to a new pump model? I'm planning to initially change the front to disc brakes with the rear to follow shortly. Any feedback would be appreciated! Thanks, Gene

joe_padavano

I'd get a pump from a Chevy one ton pickup with hydroboost. This will have the correct reservoir with the two return line fittings. I'm not sure it's any more or less reliable, just different. I've had a number of one ton trucks with hydroboost, and certainly have had no issues at all.

stokerg

Thanks Joe.

Stevec

I upgraded to hydra boost brakes and let me tell ya I should have done it a long time ago. My engine doesn't make a lot of vacuum I swapped master cylinders,installed vacuum pumps,vacuum reservoirs and my brakes always stunk!

I bought a complete hydra boost kit from CPP which gave me everything to install and my brakes are awesome! Plenty of pressure at all 4 calipers and with the original power steering pump. Easy install and I highly recommend it!

stokerg

Thanks STEVE. I appreciate the feedback. Where is CCP? Gene

Stevec

CPP or Classic Performance Products,just google them or they are in most of the hot rod-muscle car magazines

oddball

I made the conversion on my '72 Supreme due to low vacuum, and it has worked out well.

There are a lot of ways to do it. As usual, cheaper methods require more creativity and modification, and out-of-the-box methods are quite a bit more expensive.

Other vendors are Talon Hydraulics, and there's some folks on eBay. 'sterlingworth16' on eBay makes custom brackets.

Here's the high points, from pedal forward:

You need to connect the pedal to the hydroboost. I don't know how the '57 stock pedal works, but many (if not all) factory hydroboosts use a retained eyelet. Vendors will replace that with a threaded rod and clevis. The retention is a pretty good crimp, so this can be a bear. I initially used the vacuum boost connection on the brake pedal and had an exceptionally low and soft brake pedal. I switch to the manual brake connection - higher on the pedal - and it's much better. I'll probably drill one or two holes inbetween to further fine tune the pedal feel.

The hydroboost needs to be mounted. Most come with an application specific bracket. All units use a very large nut, installed very tightly, to retain the bracket. A special socket is required to permit the pushrod to pass through. Vendors will install a more appropriate bracket for you. Sterlingworth16 makes some really nice low profile brackets. I got a boost with the same mounting pattern as the common GM vacuum boosters, then used vacuum booster brackets from MBM (aka Pirate Jack).

Master cylinder mounting: The booster uses the common GM mounting, so that's easy. The pushrod may or may not match the master cylinder. You can check by some careful measurements, or just mount the thing. The pushrod should NOT contact the master cylinder - there should be just a bit of pedal travel to make the pushrod contact the master. There have been cases of long pushrods with shallow hole masters - the brakes are continuously engaged and the refill holes are never exposed. Talon can make custom pushrods if necessary. I went that route in order to use a master from the mid 80's Dodge pickups.

Pressure hoses. Hydroboosts uses metric fittings. Fluid goes from the pump to the boost. The bypass goes from the boost to the gear, then there are two returns. The pressure hoses MUST be appropriately rated (oil, 1500+ PSI). I used Aeroquip high pressure hose. You can also do enough hunting and find factory fit-ish stuff. The high dollar kits will include aftermarket hose (aeroquip or similar). I used metric to AN fittings and -6 hose. Make sure to get the fittings on the boost correct! If hooked up backwards then it will kinda-sorta work.

Return lines: The returns must not interfere with each other. The gear continuously flows fluid, while the booster only flows when the brakes are actuated. The problem is *any* pressure on the booster return line will engage the brakes. The simple way is to just use a basic T fitting - the key is the gear and the reservoir must be on the run, with the booster on the branch. Or you can get a reservoir with two return fittings. Or use a fuel Y block.

Reservoirs: I bought in to having an external reservoir with fancy baffling and whatnot to cut down on foaming. Didn't help, and the N-style pumps were problematic. Went back to just a stock can-o-ham pump and it's working fine. The hype is that aerated fluid causes the brakes to act poorly, so you want a reservoir that helps get the air out of the fluid. This is true, but time also works. In the end, the brakes are just spongy and grabby right after having the fluid system open until the fluid settles down.

Cooler: A cooler becomes more important with a boost. Put the cooler on the gear return line, before it joins in with the boost return. Note that the return line can have pressure spikes on turn lock, so a quality cooler is necessary. Some folks discourage plate-style coolers because they can be more fragile than tube-style. Of course OEMs are using plate style PS coolers now.

Pump: A common Saginaw pump is fine. The pumps re-valved for Mustang racks won't work, but you'd know if you had one of those. The rock crawler community does a lot of pump customization, but their needs are far greater than ours. There are arguments about specific flow rates, pressures and valving for hydroboost, which IMO mostly don't matter unless you are road racing.


The feel of the brakes is very different than vacuum. They still modulate well, although right now I have a severe tip-in point. Leaning real hard on the brakes loads up the power steering pump, which can kill the engine, so make sure your idle is very strong. I'm not convinced hydro is any more or less reliable - just different. It is much less space on the firewall, and works well on low-vacuum engines.

Good luck!

joe_padavano

That's an outstanding write-up. Thanks for taking the time to post it.

stokerg

Thanks for the info!! That was more quality information than I've read in any article on Hydroboost. I'm especially interested in the specifics on reservoir and cooling requirements. I'm sure I'll pick your brain along the way but your response was greatly appreciated. Have a wonderful Christmas!