Crank your boost up 25lbs.Run to 100mph Then jam your brakes on in a quick emergency stop. I like you so make sure you have alot of stopping room or your foot is near an emergency brake :biggrin:
PM vs. VAC
- Thread starter jcawley3
- Start date
Crank your boost up 25lbs.Run to 100mph Then jam your brakes on in a quick emergency stop. I like you so make sure you have alot of stopping room or your foot is near an emergency brake :biggrin:
I used the 18021981 check valve and it was a different color than the one that came on my NEW acdelco booster, and playing with both of them with a blow gun, the one I ordered sealed faster, and more reliably, so I assumed the gray one was built just for boosted apps., and the black one was for N/A. I guess I was wrong.
All I know is I love my vacuum brakes and I'm not switching back. EVER.
All I know is I love my vacuum brakes and I'm not switching back. EVER.
Part numbers are listed in this thread:
Vacuum Brakes - t6p.com - Turbo Buick Regal Resource
Be warned that they are very pricey. Also I don't know about the check valve being a TTA only item but I do know the one ordered seperate (gray in color) is a better working check valve than the black one that came on the booster. I still have them both and if anyone doubts it I can meet them at next year's power tour with them and they can see for themselves. Hope this helps.
bob koch
Vacuum Brakes - t6p.com - Turbo Buick Regal Resource
Be warned that they are very pricey. Also I don't know about the check valve being a TTA only item but I do know the one ordered seperate (gray in color) is a better working check valve than the black one that came on the booster. I still have them both and if anyone doubts it I can meet them at next year's power tour with them and they can see for themselves. Hope this helps.
bob koch
turbofish38
Le Pétomane
- Joined
- Dec 3, 2002
Hey Bob. The 18013429 MC is discontinued. Replaced by GM# 18030440 or Delco#18M198.
You can test that check valve other than blowing into it. Get up to boost on the highway and put your foot on the brake. See how fast you lose vacuum assist. After that let off the gas and see how quickly vacuum assist returns. I dont think it makes a difference on which check valve is used. They both do the same thing.
- Joined
- May 28, 2001
Vette, non pwr M/C, bolted directly to the firewall, pushrod modded = VERY reliable brakes on the "yellow car" @ 150+ mph...
Well bottom line if anyone needs substantial proof that the PM is a POS, just look at how General Motors DIDN'T install it on the 89 TTA.
Powermasters are like russian roulette, the more you play the more likely chance of you getting killed.
Powermasters are like russian roulette, the more you play the more likely chance of you getting killed.
turbofish38
Le Pétomane
- Joined
- Dec 3, 2002
Well I think the reason that GM(or PAS) didn't hang the PM on the TTA was because of the cost envolved. There are other cars out there with various versions of the PM. The 89-92 W bodys used a PM3 system as an option when the ABS was ordered. And than there is the Teves set up used on the high end C-bodys like Park Ave and Deville. Just like anything else it's easy to blame what you don't understand. Plus the fact that parts aren't easy to come by today. Even with some white knuckled moments in the past I would go back to a PM if I could still get the parts to rebuild it. For me it's a matter of economics. I can rebuild or replace it one part at a time a heck of a lot cheaper. I dont know if I would fork over $400-$500 for a reman'd unit.
Perhaps it was about cost and potential warranty costs. But to me, but it indicates the GM engineers and execs were quite comfortable (as were their lawyers) with the stopping performance of vacuum brakes on a turbocharged car.
Electric brakes are a bad idea, GM is not the only one to have problems w/ the power/accumulator design. 1995 Jeep cherokee w/ ABS had a massive recall and the NHTSA made Chysler give a lifetime warranty on certain parts!
How would you like to go to the dealer w/ a 12 yr old car for warranty work and see how long that takes, and how well you get treated?
84 & 85 GN had hydroboost. I have a 85 in my T. I would consider a manual. I had way too much trouble with the vacuum not working when boost is up & check valves failing, causing the boost unit to leak. Pm is expensive, however, I obtained mine for $199 at Advance auto parts a long time ago. The rebuild pm wasn't reliable enough.
BlackMetal
Active Member
- Joined
- Sep 29, 2005
I myself am considering hydroboost because I'm just not comfortable with vacuum but then people argue that if your power steering system leaks you have no steering assist or brakes. Seems like there's an arguement against every brake system and it just makes me want to leave the car in the garage.
I have an idea. How about air brakes? Off road Jeepers convert old style A/C compressors into air compresors and have on board air for trail use with air tools and inflating repaired tires.
How about we come up with some type of well regulated air braking system like large (sometimes turboed) trucks have? Kenworth and the others have been using this for years, I would guess it's reliable enough. But they sometimes do have problems.
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Any brake system is going to have problems my friends. It's the nature of the beast. You have to consider that the PowerMasters we are dealing with are high maintanence, 20yr old units. It was GM's attempt to solve a problem and it worked well...when it worked. GM doesn't design anything to last very long. Just look at your local GM service center. Brand new vehicles are in for stuff that our 20yr old Buicks wouldn't think of.
Also think about this. How many vacuum master cylinders have you known that would last 20yrs? I have personally replaced the m/c on my Jeep twice since I bought it in 98. What I believe was the original was bad when I bought it. And I keep getting cheap rebuilds from the 'Zoo'. I can't find "new" ones any more.
How about we come up with some type of well regulated air braking system like large (sometimes turboed) trucks have? Kenworth and the others have been using this for years, I would guess it's reliable enough. But they sometimes do have problems.
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Any brake system is going to have problems my friends. It's the nature of the beast. You have to consider that the PowerMasters we are dealing with are high maintanence, 20yr old units. It was GM's attempt to solve a problem and it worked well...when it worked. GM doesn't design anything to last very long. Just look at your local GM service center. Brand new vehicles are in for stuff that our 20yr old Buicks wouldn't think of.
Also think about this. How many vacuum master cylinders have you known that would last 20yrs? I have personally replaced the m/c on my Jeep twice since I bought it in 98. What I believe was the original was bad when I bought it. And I keep getting cheap rebuilds from the 'Zoo'. I can't find "new" ones any more.
turbofish38
Le Pétomane
- Joined
- Dec 3, 2002
I guess we are all forgetting that there are 200 million cars and trucks out on the road everyday. Take your pick. Vacuum,manual,electric,HB. They all have one or another. If any of these systems was total POS than there would be mass hysteria on the road. Whad'ya think? TR's are the only car with brakes? Pick the one that suits your needs and budget. You cant go wrong. Some of you guys are too paranoid.
BlackMetal
Active Member
- Joined
- Sep 29, 2005
Some of you guys are too paranoid.
Well I think it's worth being paranoid about being able to stop your car before killing yourself or someone else not to mention wrecking a 20 year old collector's car.
If I can find the parts I think I'll be doing a manual conversion. Don't drive my car every day so I won't mind the extra leg effort. No vacuum to leak, no accumulators to fail. Just a little tricky to find the parts.
imjoesnuffy
I just break stuff!
- Joined
- Sep 13, 2005
Interesting reading here. I have a powermaster setup on my 85 GN. Any signs and symptoms of it going out? Other than the pedal hitting the floor?
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
The pedal hard as a rock with no slowin of the car, among sevral others do a search
My brother has 2 buicks he has a problem with one powerbrake, the other one so far works perfect, he sold the car with the brake problem its getting fixed as we speak.
Mine has vacuum i bought the car with them already installed so i cant tell a difference between it & my truck except my buick is a little sluggish spongy but im use to it he gets in it he's use to it. I go to the track and Stop fine i have slotted rotters & low dust brake pads. but i dont plan on going over a 100 on a highway unless its straight , no cars comming or on the track.
i have to push the pedal a little harder but my car do stop well for me at the track.
But i get in his blue car with the power brakes Mannnnnn those things stops almost instantly!! But not that great a difference be tween the 2 to me. what you need to do is drive in a buddy's car that has both one with a vac. & other with the pm. & see if its something you could get use to.
The only problem i would have with the pwermast. is that what if your spouse or girlfriend gets in the car, and she's NOT USE TO IT if it stops all of a sudden because a fuse blow or something her legs are not as strong as ours,,, much less as predictable as we are concerning evasive action,
(e brakes_ swerving out of danger etc.) The only thing she's gonna say is the car didnt have ANY BRAKES as your car is totaled or someone elses car.
Its scary to me just to think about it,, you'd just better be on your job (preventive maint), or worry less by going vacuum....just my 2.
Mine has vacuum i bought the car with them already installed so i cant tell a difference between it & my truck except my buick is a little sluggish spongy but im use to it he gets in it he's use to it. I go to the track and Stop fine i have slotted rotters & low dust brake pads. but i dont plan on going over a 100 on a highway unless its straight , no cars comming or on the track.
i have to push the pedal a little harder but my car do stop well for me at the track.
But i get in his blue car with the power brakes Mannnnnn those things stops almost instantly!! But not that great a difference be tween the 2 to me. what you need to do is drive in a buddy's car that has both one with a vac. & other with the pm. & see if its something you could get use to.
The only problem i would have with the pwermast. is that what if your spouse or girlfriend gets in the car, and she's NOT USE TO IT if it stops all of a sudden because a fuse blow or something her legs are not as strong as ours,,, much less as predictable as we are concerning evasive action,
(e brakes_ swerving out of danger etc.) The only thing she's gonna say is the car didnt have ANY BRAKES as your car is totaled or someone elses car.
Its scary to me just to think about it,, you'd just better be on your job (preventive maint), or worry less by going vacuum....just my 2.
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