Brake Response of Hydroboost vs PM vs Vacuum

Nascar83Fan

Active Member
I know, someone else had quoted one of my previous posts in the thread and made mention of it. So that's why the last previous post i made was in response of that.


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TexasT

Texas, Where are you from
Unless you stall out, then you have almost zero brakes!!!

I have H/B on my diesel and it's a lot harder to stop when and if the H/B goes out, it feels like the good ole days of single cylinder non power M/C 's when the seal blows out.

Other than that they work great.
Maybe you need to tune your car up if you are having problems with the engine stalling. I've thrown the idler pulley. There are brakes, just not power brakes. For the hydroboost superior braking , ill take my chances.

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V6Turbo

Member
Thanks folks for all the positive
responses.

Thinking of doing this myself and want the easiest install.

I've researched the similar threads and may go with the 84/85 hb set up and I assume I can get most of the parts from OReilly or autozone.

Do I need to do much modification to the mounts as compared with astrovan conversion?

Can someone send me to the DIY link?..There are so many threads on hydroboost and cant seem To Find the instructions.

Do the OReilly parts hb have external accumulator.

I've contacted powerbrakes.net and they we're helpfull..but the bosch unit seemed a little pricey or application is overkill for what I need. They do look nice though and offer the install.

I just want to stop fast and hold boost based on my mods.

Thanks in advance.
 

Nascar83Fan

Active Member
Here's pictures of the Hydroboost setup on my car in question.
ImageUploadedByTurboBuick1414878421.117702.jpg


ImageUploadedByTurboBuick1414878452.818377.jpg


ImageUploadedByTurboBuick1414878528.757784.jpg


ImageUploadedByTurboBuick1414878634.007202.jpg


Any idea what that sticker of CY means if it applies to my Hydroboost unit or not?

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robzombie

Well-Known Member
Maybe you need to tune your car up if you are having problems with the engine stalling. I've thrown the idler pulley. There are brakes, just not power brakes. For the hydroboost superior braking , ill take my chances.

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Like I stated in my post it happened while driving my [diesel] truck. It wasn't the tune that caused it to stall, it was a faulty PMD/FSD.

I still use the P/M system on my car and have no issues with it as of yet, but I can see why the H/B system is a good upgrade for the higher line pressures that are attainable.

The only problem with either of these systems is that you have no [real] brakes when the hydraulic assist is disabled for whatever reason or cause.

You may have more luck stopping you're 3,500 lb. car than I do with my 7,000+lb. truck when it fails. I was just relaying my experience with a H/B system and the effects when you lose the power steering pump. You lose both the steering and brakes together with a H/B system which could be a handful if you are trying to stop while in a turn or need to turn to avoid ramming the car in front of you.

Atleast with the vacumn system you get one maybe two pumps on the pedal before they go hard as a rock.

As with any performance mods there are trade offs that should be considered and what is most important to you will decide which is best for your driving style or use.
 
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TexasT

Texas, Where are you from
Like I stated in my post it happened while driving my [diesel] truck. It wasn't the tune that caused it to stall, it was a faulty PMD/FSD.

I still use the P/M system on my car and have no issues with it as of yet, but I can see why the H/B system is a good upgrade for the higher line pressures that are attainable.

The only problem with either of these systems is that you have no [real] brakes when the hydraulic assist is disabled for whatever reason or cause.

You may have more luck stopping you're 3,500 lb. car than I do with my 7,000+lb. truck when it fails. I was just relaying my experience with a H/B system and the effects when you lose the power steering pump. You lose both the steering and brakes together with a H/B system which could be a handful if you are trying to stop while in a turn or need to turn to avoid ramming the car in front you.

Atleast with the vacumn system you get one maybe two pumps on the pedal before they go hard as a rock.

As with any performance mods there are trade offs that should be considered and what is most important to you will decide which is best for your driving style or use.
I doubt our k2500 Suburban weighs in at 7k# but it stopped when it chucked the idler pulley, and it didnt have pwr steering either. Only happened once, so I keep an eye on the belt and idler and tensioner pulleys. You push the pedal with your foot/leg and it applies the brakes, just takes more effort without the power assist.

I love the h-boost on my Regal. It'll stop circles around the powermaster.
 

captndave737

Well-Known Member
11 years and 100k of trouble free use out of my HB. Nearly wrecked the car pulling into a parking space when a 2 month old PM went out. Tried vacuum and though they were reliable I've had a few instances where I would have crashed due to the slow response where the HB brought me to a rapid stop.
 

TurboTnZ06

Go on red!
I'm running a '81 Caddy Eldorado new Fenco master on my 84/85 GN hydrobooster. Has the plastic modern look to it, not a 1940's style cast iron master that looks like it weighs 30#'s.
 

Roger

Active Member
PM went out. Tried vacuum, had MANY issues - however other local owners like the vacuum. Found an 84 & installed it - very pleased, it is nowadays more popular & would cost less than the almost $600 I have in it (rebuilt the unit, braided stainless lines, etc). Have heard of going non power boost - it would be the simplest, however I'm pleased with the HB.
 

Undercover87T

Maryland MAGNA Rep
Staff member
Have a vacuum booster and Aerospace brakes on my car. No Issues stopping but I do wish it held more boost at the track. Does the hydroboost system have any negative affect on the PS pump?
 

TexasT

Texas, Where are you from
I didn't like that they cut the original lines. It isn't that difficult to r&r a couple things and put lines on. Just my preference. Mine does work like the one in the vid. Mad braking skillz. I also dont like the idea of that giant iron piece hanging off the end and stressing the unit. So I went with the aluminium and plastic piece.

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TurboTnZ06

Go on red!
Just looking at my powerlogger, I logged 12.4 psi boost at 4000 rpm on the foot brake with hydroboost at 2.64 TPS building boost before WOT. The one time at the track I left earlier at 10 psi boost I pulled a 1.51 60 foot.
 
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