Back in the game, and need a little advice...


Guys, I am asking for a quick opinion. I have a nice 87 GN that I drive regularly. I have simple mods like extender chip, MAF translator, etc. I don't drag race, just a boosted blast from time to time. This car is dear to me. My powermaster is working, but I want to upgrade before something awful happens. I have researched hydroboost and vacuum brakes. Which do you guys prefer based on personal experience?

Thanks for the help


I appreciate the input Texas T. I also have a wife and two kids. (one in college) I have waited 30 years to have this car and want to enjoy it!


Texas, Where are you from
Right there with ya. Wife and Four children though three have ventured out on their own. I am the apitomy of budget guy. I did the hydroboost because i didn't have to hunt up a different brake pedal.


Active Member
I have hydroboost ,and it came o e on my originally carbureted ttype. If I had to do a conversion, it would be to vacuum because of cost. Be certain to buy the vacuum block with the extra port for this job. You can redrill the pedal if you have to, or any vacuum brake gbody can provide you with the right pedal.


Thanks all. I work five miles from Beech Bend Raceway in Bowling Green KY. Hope to see some of you folks at the GS Nats
in May!


Well-Known Member
I've had all three.
  1. The 28k mile white T had OEM Powermaster - 15K+ miles put on & never failed me 'til I decided to sell the car. Then it started to show the brake light periodically. I did not want to sell the car to someone only to find out later he/she wrinkled that beautiful car up on the way home. Problem solved when I replaced the accumulator with a known good unit tested by Richard Clark. The brakes on that car had been flushed yearly over the 10+ years I owned it. Judge for yourself.
  2. Had a 100K mile column shift modded car with vacuum set up I added. It never felt weak. Always stopped on a dime and I drove the hell out of that car. No 1/4 mile dragstrips but lots of street miles. I loved it. All the parts put on were new or rebuilt. Best bang for the buck.
  3. The totally ground up rebuilt project car (the only one I have left) - got brand new or rebuilt Powerboost parts. Knock on wood - It grips great but these days only gets a few miles each year. I love it too. It does make groaning noises occasionally and I can tell when I apply the brakes when starting up & maneuvering around (like out of a parking lot or close quarters). Otherwise no complaints!
I had two other Turbo Regals with the Powermaster that I had no problems with while I owned them.

All have their good points - all were good mostly with the one low mile car having a reliability issue that got fixed easily. I guess I would choose the vacuum set done with new or rebuilt parts for your kind of driving. You drive yours the way I do - mostly EZ duz it with an occasional 'ego boost.' Your choice keep or sell your OEM brake unit to cover part of your expenses.

I guess I'm not much help - just a few things that come to mind as I think of each different set up.


Short Guy
Vacuum is the second simplest swap.

The order of complexity and cost:

4) Keep the Powermaster. most expensive, most risky
3) Hydroboost. Expensive, complex. more weight, puts extra load on the power steering pump
2) Vacuum - cheap enough, make sure you put a good check valve in the vacuum line. the plastic ones that come with the boosters like to leak, and pressurized booster doesn't boost.
1) Manual - uses same pedal ratio as the PowerMaster. Fewer parts. Same pedal every time, no matter what. Wilwood's 15/16" master bolts right to the powermaster bracket and comes with the adapters to connect it directly to the factory lines.


Wrinkled Member
Vacuum with a dual diaphragm G-body Monte Carlo booster & master cylinder. Locate a vacuum brake G-body brake pedal & swap pedals, or modify original pedal by drilling new hole. A "T" can be spliced into the existing large vacuum line, or purchase a new vacuum block with extra port.

There are some complete vacuum brake kits available from vendors.

Vacuum is the easiest, cleanest & most cost effective.


Thanks again, you guys. Based on the fact that I drive this thing whenever possible and never drag, vacuum looks like the one for me. Reliability is the name of the game in this case.


Well-Known Member
It seems many have had good luck with the vacuum conversion, make sure to get the right booster. Many years ago I did a vacuum conversion and bought the kit from a good vendor. The brakes were horrible. Barely adequate. Also, get the right vacuum block. On my current buick I went with the hydroboost. One of the best mods I did. The brakes are always there, and with the stock dinky rotors, still plenty for an emergency stop. Not saying the right vacuum setup won't work, just make sure you get the right setup, especially if the rest of the system is going to be stock.


Tall Unvaccinated Chinese Guy
The main reasons people install vacuum brakes instead of hydro boost are simplicity and cost. Presonally, I would install manual brakes for those reasons before I ever went vacuum.

"TTA had vacuum brakes which worked fine."
True, and I don't know the pedal dimensions (leverage), brake caliper piston area, and vehicle weight.


Wrinkled Member
...Vacuum is the easiest, cleanest & most cost effective.

EDIT: Guess I should revise this post. Sounds like a high quality manual brake conversion may be "...the easiest, cleanest & most cost effective."

Not sure if a proper manual master cylinder was as readily available back when I converted to vacuum assist.