87 GN PowerMaster conversion to hydroboost questions.

C

CanMove

Active Member
Joined
Sep 9, 2007
Well my brakes took a **** again 87 GN with 26K original miles.
I'm going to ditch the power master brake set up to a hydro boost because i plan on doing some mods to the motor and i read if i plan on doing that to stay away from the vacuum assisted because i will not have sufficient vacuum.. If i was gonna keep motor stock i would be fine with vacuum.
Is this correct info?? Am i making the right choice..
I was on Kirban's sight looking at the prices for the conversion units and the hydro is about double the price of the $350 for vacuum and about $650 for the hydro set up. Is there anywhere cheaper that i can get complete conversion kits?
I also am curious if anyone else that's reading this could tell me what i should expect price wise to get this hydro kit and have it installed.. basically what did you guys pay to have the conversion done..

Thanks for your time...
Richard
 
interested in the PM setup for parts. PM me please.

Thanks
Bryan
 
I bought Kirban's hydro kit with the SS high pressure hoses and billet backing plate last year. Not sure if he still sells that package, but it's a great kit. I also bought the Baer 1 1/8 polished master cylinder. Wanted something nicer then the MC it came with. The Hydratech kit is a really good quality kit. With just a little bit of research on the Internet you'll see what I mean. Won't find any better quality out there. CPP makes a kit too. http://www.classicperform.com/Store2/Hydraulic-Brake-Assist-Systems.htm Pretty much the same money. I've read people using the Astro mini van brake booster. Not really sure though. I don't have many hang-ups, but when it comes to my brakes, I want the shit right..... I know there's a bunch of threads out there on this topic. I'm sure others with much more knowledge then myself will respond. Try using the search, too. Good luck.
 
Click on the hydroboost link in my signature for a how-to. It isn't terribly difficult if you are mechanically inclined. I am just a shade-tree mechanic and it was not bad at all. Turbonut85 had posted his experience years ago and I followed his recipe for a conversion on the cheap. I think my conversion was right at $300. It all depends on what you want to spend. There's no denying the quality of the Kirban kits or others out there. Mine has worked flawlessly on remanufactured parts for years now. If I could do it again I would pick a different master cylinder but I painted my iron unit black and it looks good.
 
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these arent chebby SB's that can be under 12in/hg vac with lopey cams
even modded with what would be considered a big cam for a v6 you should be fine
my 87ttop has gn1 ported alums/tall valves/race intake and high lift 224 solid roller cam and pulls 15in/hg of vac at idle 850rpm.. vac brakes
 
chris kirk said:
I bought Kirban's hydro kit with the SS high pressure hoses and billet backing plate last year. Not sure if he still sells that package, but it's a great kit. I also bought the Baer 1 1/8 polished master cylinder. Wanted something nicer then the MC it came with. The Hydratech kit is a really good quality kit. With just a little bit of research on the Internet you'll see what I mean. Won't find any better quality out there. CPP makes a kit too. http://www.classicperform.com/Store2/Hydraulic-Brake-Assist-Systems.htm Pretty much the same money. I've read people using the Astro mini van brake booster. Not really sure though. I don't have many hang-ups, but when it comes to my brakes, I want the shit right..... I know there's a bunch of threads out there on this topic. I'm sure others with much more knowledge then myself will respond. Try using the search, too. Good luck.
Click to expand...
man u helped out a ton. thanks for your time and the info... i will keep u posted on what i end up doing..
 
I pieced my kit together with reman parts from Napa and I think i have around $300 in to mine. I love it! The pedal is slightly hard and my power steering pump hates me now. I need to do some research on what to do with getting the pedal feel a little softer and I read a post about someone having a company out of Anderson CA. rebuilding the power steering pump to compensate for the Hydro boost and it ran about $100. Over all really happy with the set up, just make sur
 
Easily the best most functional modification I've done to my car. Who can argue with better stopping ability?
http://www.ihadav8.com/forum/index.php?topic=4228.0

I did like some above. I followed the thread, ordered mostly from rockauto.com and wrenched until it worked. And work it does, at least for me.
Let us know how you do.

Sent from my HTC PH39100 using Tapatalk
 
TexasT said:
Easily the best most functional modification I've done to my car. Who can argue with better stopping ability?
http://www.ihadav8.com/forum/index.php?topic=4228.0

I did like some above. I followed the thread, ordered mostly from rockauto.com and wrenched until it worked. And work it does, at least for me.
Let us know how you do.

Sent from my HTC PH39100 using Tapatalk
Click to expand...

This is a hydro boost set up i think im going to a vac set up.. any threads on that??? Thanks for your time
 
You will have to search. I think hydroboost is better but there are plenty of owners who went vac conversion. Not really much to it though you do need a vac pedal or move the pin on your powermaster pedal. Then you need a vac booster and a master cylinder. As with any operation that opens the brake lines you will need to bleed the brake system.

Sent from my HTC PH39100 using Tapatalk
 
kirbdawg69 said:
I pieced my kit together with reman parts from Napa and I think i have around $300 in to mine. I love it! The pedal is slightly hard and my power steering pump hates me now. I need to do some research on what to do with getting the pedal feel a little softer and I read a post about someone having a company out of Anderson CA. rebuilding the power steering pump to compensate for the Hydro boost and it ran about $100. Over all really happy with the set up, just make sur
Click to expand...


Interested in hearing about the power steering pump modifications. What exactly did they do?
Can you post the name and or web address / contact info for this company.
Would it be Lee Pumps in Sun Valley CA?

Thanks
 
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I did lots of research on this for some time. As one user already posted, unless you're going with some crazy setup on your LC2, a vacuum brake system will work just fine and it's simple. I just converted my wife's GN's brakes yesterday. It's a pain lying upside-down in the driver's seat with your head under the dash changing out the brake pedal but it wasn't difficult as a whole. My total cost was $120.00. Price for a brake pedal, vacuum booster and master cylinder from a 1983 Pontiac Grand Prix = $100.00 + tax already pulled from local auto yard. A little clean-up, black spray paint, vacuum line, DOT-3 brake fluid = $120.00 + 6hrs of my time and none of it difficult. I already had a TTA style vacuum block so I was covered there. Car runs perfectly and stops nicely. I should never again see that annoying red BRAKE light on the dash anymore. If Pontiac felt TTAs could stop well (and they do, I had one) with vacuum it's good enough for her GN. In short - POWER MASTER SUCKS.

BTW, anyone want to by an original Grand National (non working) full Power Master unit? It looks damned near brand new.
 
1KWIKSIX said:
Interested in hearing about the power steering pump modifications. What exactly did they do?
Can you post the name and or web address / contact info for this company.
Would it be Lee Pumps in Sun Valley CA?

Thanks
Click to expand...

Man I spent an hour last night looking for the thead and couldnt find it. I figured it was going to be easy as I plan on doing it myself, and nothing.... cant find it. Kinda sucks as I need to do this.
 
Stick with it. The vac conversion is soooo worth it. Did mine 2 years ago and hate myself for not doing it Sooner. Its a bolt on swap fairly easy but a bit of a pain under the dash. Buy the pedal master, booster. And vac block. All readily available here,internet and napa. Do it!
 
Can't agree with gsgnnut any more. Had the GN out today with the 1983 Pontiac Grand Prix brakes and WOW, the confidence it brings knowing you'll have 100% brake power is indescribable. I should have done this to all my Turbo Regals looooong ago. My D84 Turbo-T is next.
 
Just a question for those with Vac brakes. Im on my 3rd MC and panic stops have a completely different brake feel than normal braking and I would hate to actually need a panic stop. Is this inherent in vac systems? Im collecting parts for a hydroboost in hopes for something more reliable.
 
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