how many people are using vacuum brakes?
- Thread starter the wrath
- Start date
I understand that. Which is why I made the statements I did, quantifying when vacuum brakes would be good, and when not, on a T/R.
I do a lot of drag racing, but without a trans brake, so I need a lot of dependable holding power on the line. Enough to build more than 15# of boost on the line, and not have to worry about pushing through the lights (until I'm ready).
The number of people that can do that, reliably, repeatably, on vacuum brake systems are in fact (truth be told) very few and far between.
Like I said earlier. There's a place for vacuum conversions on our cars, but there's also not.
LIne locks are for burnouts, NOT for locking the rears!!!!
I have a line lock, and use it as it's meant to be used. Yes, it will lock the fronts, but with sticky rear tires I can push the front (locked) tires down the track easilly with only about 5# of boost.
NOT enough to hold the car in place, and NOT what a line lock is meant to do.
I have a line lock, and use it as it's meant to be used. Yes, it will lock the fronts, but with sticky rear tires I can push the front (locked) tires down the track easilly with only about 5# of boost.
NOT enough to hold the car in place, and NOT what a line lock is meant to do.
Red Regal T
Senior Member
- Joined
- May 24, 2001
Well, like I said, holding boost at the line is way down on my priority list. There's been plenty of posts on this subject and plenty of guys claim to hold 10 lbs of boost and more with vacuum brakes. If this is a priority for anyone, do what ya gotta do. I'm about dependable brakes that are cheap to maintain. End of story.
They didn't seem that rare at BG.
When is there NOT a place for vacuum brakes?. I can't wait to hear about when it's perfered to have a system that in failure mode that effectively leaves you with NO brakes.
I guess the engineers at GM were wrong in selecting vac brakes for the TTA....
I'm sure some of you are familar with Jack Cotton. He has been racing turbo buicks for years. His race car has a vacuum brake booster. There is also no vacuum cannister. I have inspected his car extensively and talked with him numerous times. Works fine for him and this is a RACE car.
Conrad Carter
ps...I have vacuum brake booster / master cylinder form a 87 normally aspired Regal. Stops fine!
Conrad Carter
ps...I have vacuum brake booster / master cylinder form a 87 normally aspired Regal. Stops fine!
So, you didn't ask him about his trans brake then? You don't seriously think Jack Cottons car launches off a foot brake now do you?
BTW, nobody's disputing whether or not the car stops just fine. I driven a few, they work just fine for stopping.
Ya'll win. My 19 and 18 year old Power Masters are junk (but still working just fine thank you).
POWERBRAKEBOB
Banned
- Joined
- Mar 28, 2005
HYDROBOOST SYSTEMS
HI! GUYS! Well the hydroboost controversy continues. If a vacuum power brake unit would provide 1200psi when the manifold is in boost conditon instead of vacuum, Buick would have installed the same Delco boosters on all Regals, including turbocharged ones. Vacuum boosters need vacuum to work, no secret. They are rated to operate at 20" of vacuum. When vacuum drops to 15", the booster loses 40% of it's power. At 10" of vacuum, there is no boost over a manual brake system, due to the pedal ratio difference. We actually love those Delco boosters for BB Chevelle and 55 Chevy applications. They clear valve covers and are only 8 3/4" dia. They work well "with vacuum" on those cars. We are seeing guys stepping up the horsepower with 572 motors, Hemi's, giant camshafts, big blowers, overdrive transmissions, etc. The Hydroboost runs off of the power steering pump. Therefore, NO VACUUM IS INVOLVED! In the case of the Buick turbo cars, the pump is spinning faster as the RPM and the boost builds. The hydroboost can build up to 2000psi and lock the brakes even tighter with higher RPM. The car explodes off of the line at 10lbs of boost! It just works. Hydroboosts have been around 30 years and can stop 14,000 lb vehicles. The powermasters worked when they were new, but they use phenolic vanes in their pump, and they pump brake fluid, which has no lubricity. The vanes wear out, and then cannot generate the 2400 psi to the accumulotor. The pump runs continuouly, trying to reach the shut off point of the switch. It just wears itself out even faster. The basic powermaster is rebuildable, but the pump and switch assy are not rebuildable. We are installing Hydroboosts on all vehicles that have a pump, and even adding a pump to the motor to power others. The Hydroboost is compact, and is guaranteed to work. We were appointed as the only outside distributor (other than the automakers) by Bosch to retro fit hydroboosts to other v ehicles. They are viewable on our website at POWERBRAKESERVICES.COM Click on "company info" for photos.
HI! GUYS! Well the hydroboost controversy continues. If a vacuum power brake unit would provide 1200psi when the manifold is in boost conditon instead of vacuum, Buick would have installed the same Delco boosters on all Regals, including turbocharged ones. Vacuum boosters need vacuum to work, no secret. They are rated to operate at 20" of vacuum. When vacuum drops to 15", the booster loses 40% of it's power. At 10" of vacuum, there is no boost over a manual brake system, due to the pedal ratio difference. We actually love those Delco boosters for BB Chevelle and 55 Chevy applications. They clear valve covers and are only 8 3/4" dia. They work well "with vacuum" on those cars. We are seeing guys stepping up the horsepower with 572 motors, Hemi's, giant camshafts, big blowers, overdrive transmissions, etc. The Hydroboost runs off of the power steering pump. Therefore, NO VACUUM IS INVOLVED! In the case of the Buick turbo cars, the pump is spinning faster as the RPM and the boost builds. The hydroboost can build up to 2000psi and lock the brakes even tighter with higher RPM. The car explodes off of the line at 10lbs of boost! It just works. Hydroboosts have been around 30 years and can stop 14,000 lb vehicles. The powermasters worked when they were new, but they use phenolic vanes in their pump, and they pump brake fluid, which has no lubricity. The vanes wear out, and then cannot generate the 2400 psi to the accumulotor. The pump runs continuouly, trying to reach the shut off point of the switch. It just wears itself out even faster. The basic powermaster is rebuildable, but the pump and switch assy are not rebuildable. We are installing Hydroboosts on all vehicles that have a pump, and even adding a pump to the motor to power others. The Hydroboost is compact, and is guaranteed to work. We were appointed as the only outside distributor (other than the automakers) by Bosch to retro fit hydroboosts to other v ehicles. They are viewable on our website at POWERBRAKESERVICES.COM Click on "company info" for photos.
Re: HYDROBOOST SYSTEMS
LOL, no one had mentioned them until now.
How much are they?.
Pressure is only a major issue when using too small of capacity of brakes. So while you can crutch a inadequate system together, the penalty of failure goes up exponentially.
I do believe your percentage of effectiveness per amount of vacuum aren't very accurate. As long as there is air flow thur the booster, it will develope a mechanical assist. So even at say 90 K/Pa, with enough volume of flow, there'd still be full or a majority of braking available.
Not to mention if vac's were such a bad idea, GM sure wouldn't have used them in the FINAL Turbo Buick application.
LOL, no one had mentioned them until now.
How much are they?.
Pressure is only a major issue when using too small of capacity of brakes. So while you can crutch a inadequate system together, the penalty of failure goes up exponentially.
I do believe your percentage of effectiveness per amount of vacuum aren't very accurate. As long as there is air flow thur the booster, it will develope a mechanical assist. So even at say 90 K/Pa, with enough volume of flow, there'd still be full or a majority of braking available.
Not to mention if vac's were such a bad idea, GM sure wouldn't have used them in the FINAL Turbo Buick application.
BoostKillsStres
TIRE-FRYER VIA HAIR-DRYER
- Joined
- May 25, 2001
I know a friend of mine had a vac system on a non TR with a reserve cannister and since the car didn't make much vacuum he added a little 12v vacuum pump off some import car I believe. That gave him very nice brakes all the time. I'm sure there are several brands of cars out there that came w/ those switching vacuum pumps, just a matter of finding them. That should cure or certainly help the vac conversion people needing a reserve when in boost.
POWERBRAKEBOB
Banned
- Joined
- Mar 28, 2005
HYDROBOOST SOME MORE
Thanks for that. Yes there are vacuum braked turbo cars out there, (ie) 300z's for example, but the gn is a heavy car. Iknow you guys keep pointing to the TTA, but GN's are not stopping. If everyone was happy with stock GN brakes, there would be no need for this forum. Obviously, there is some need not being addressed. The GN is heavy (compared to Japanese turbo cars) and fast. At the time of the 80's fuel shortage, GM downsized all their cars and with the dim future of horsepower, then, they also downsized the brakes, the motors, and the transmissions.(as you know). The TTA also had 2.5" rear calipers, compared to th GN's 3/4" wheel cyl. Big difference. PSI is "pressure per square inch" Line pressure multiplied by the number of square inches at the wheel cyl or caliper. The Hydroboost can generate 2000PSI times your square inches. The new "Thing" now is the "drifter" racing. something we did since the sixties, but now cool with the import guys. They see the hydroboost as the thing to be able to ride the brake and the throttle (under turbo boost) to heel and toe the car thru the turns rapidly. We are being filmed for both Horsepower T.V. and TRUCKS! T.V. Chevelle/Camaro and Rock Crawler, respectively. Summit racing has approached us to add to their catalog. If there are any GN's local to Long Beach, CA., We would be happy to do a stopping distance test to match ANY other brake system. We are doing such a test with Street Rodder magazine at Fontana on a 40 Ford woody. We are very aware of the power and limitations of vacuum boosters, having been a rebuilder for 55 years. We have been modifying them for use with the handicapped for 40 years. They still need vacuum!
Thanks for that. Yes there are vacuum braked turbo cars out there, (ie) 300z's for example, but the gn is a heavy car. Iknow you guys keep pointing to the TTA, but GN's are not stopping. If everyone was happy with stock GN brakes, there would be no need for this forum. Obviously, there is some need not being addressed. The GN is heavy (compared to Japanese turbo cars) and fast. At the time of the 80's fuel shortage, GM downsized all their cars and with the dim future of horsepower, then, they also downsized the brakes, the motors, and the transmissions.(as you know). The TTA also had 2.5" rear calipers, compared to th GN's 3/4" wheel cyl. Big difference. PSI is "pressure per square inch" Line pressure multiplied by the number of square inches at the wheel cyl or caliper. The Hydroboost can generate 2000PSI times your square inches. The new "Thing" now is the "drifter" racing. something we did since the sixties, but now cool with the import guys. They see the hydroboost as the thing to be able to ride the brake and the throttle (under turbo boost) to heel and toe the car thru the turns rapidly. We are being filmed for both Horsepower T.V. and TRUCKS! T.V. Chevelle/Camaro and Rock Crawler, respectively. Summit racing has approached us to add to their catalog. If there are any GN's local to Long Beach, CA., We would be happy to do a stopping distance test to match ANY other brake system. We are doing such a test with Street Rodder magazine at Fontana on a 40 Ford woody. We are very aware of the power and limitations of vacuum boosters, having been a rebuilder for 55 years. We have been modifying them for use with the handicapped for 40 years. They still need vacuum!
Re: HYDROBOOST SOME MORE
There's not that much difference in weight between a GN, and TTA.
The problem is sweep area, and the ability to deal with the thermal loading. All the line pressure in the world isn't worth a hoot, if the fluid is boiling. For a performance enhanced GN or TTA, you need big fat rotors to be able to sink the heat, so that it doesn't get passed into the caliper/fluid.
Add some 02 Camaro rotors, and calipers, and then the brakes are actually in proportion to the performance of the car.
Band Aiding brakes, is an accident waiting to happen.
Not to mention the **BIG** deal with going to vacuums is that in the event of failure, YOU still can STOP the car. The more you rely on mechanical assist, the ****LESS**** stopping ability you have when the system fails.
There's not that much difference in weight between a GN, and TTA.
The problem is sweep area, and the ability to deal with the thermal loading. All the line pressure in the world isn't worth a hoot, if the fluid is boiling. For a performance enhanced GN or TTA, you need big fat rotors to be able to sink the heat, so that it doesn't get passed into the caliper/fluid.
Add some 02 Camaro rotors, and calipers, and then the brakes are actually in proportion to the performance of the car.
Band Aiding brakes, is an accident waiting to happen.
Not to mention the **BIG** deal with going to vacuums is that in the event of failure, YOU still can STOP the car. The more you rely on mechanical assist, the ****LESS**** stopping ability you have when the system fails.
Red Regal T
Senior Member
- Joined
- May 24, 2001
Hey Bruce.........I love those front brakes you put on your car. You'd think there'd be more conversation about the 98 to 02 LS1 conversion. I've saved most of the info and am going to start getting parts. Maybe by next year I'll have them on.
Re: HYDROBOOST SOME MORE
I don't think you're going to convince them unfortunately.
I would have prefered the hydroboost on my GN's instead of the Powermaster, but I got what I got, and use it to my advantage. There's NO WAY I could get the clamping force I have with a vacuum system.
I can however certainly attest to the stopping power of the hydroboost system!! I have it on my Excursion, and trust me, it will haul that 8,000 lb monster down as good or better than most sedans I've driven!!
I don't think you're going to convince them unfortunately.
I would have prefered the hydroboost on my GN's instead of the Powermaster, but I got what I got, and use it to my advantage. There's NO WAY I could get the clamping force I have with a vacuum system.
I can however certainly attest to the stopping power of the hydroboost system!! I have it on my Excursion, and trust me, it will haul that 8,000 lb monster down as good or better than most sedans I've driven!!
I am running vacuum booster and master cylinder from a normally aspired 87 Regal. I also have B-car 12" front disc brakes and Baer rear disc brakes. My brake system works great on the street. I is not a drag car. If it was, I suspect I would have to go with trans brake since I strongly suspect the rear disc would not hold the car on the line if I tried to build much boost.
My car is an 84 into which I installed 87 engine/tranny. I considered keeping the hydroboost but could not figure out how to convert the power steering pump (v-belt drive) to the later serpentine drive. In fact, Bob rebuilt my hydroboost years ago and I have never re-installed it. Still have it.
Conrad Carter
ps...son's 1993 Mustang Cobra w/96 4-valve motor has hydroboost and he loves it!
My car is an 84 into which I installed 87 engine/tranny. I considered keeping the hydroboost but could not figure out how to convert the power steering pump (v-belt drive) to the later serpentine drive. In fact, Bob rebuilt my hydroboost years ago and I have never re-installed it. Still have it.
Conrad Carter
ps...son's 1993 Mustang Cobra w/96 4-valve motor has hydroboost and he loves it!
