anyone using manual brakes?

[sackracing]

if so, how well do they work on the street? not for daily driving, but to cruises and stuff. how easy is it to stage the car at the track with them?

 

[Nick Micale]

I have used manual brakes on my race car for years and they are great! No vac booster in the way or stupid PM to fail at 130 + MPH. [Yes it did! ]

However, after more than 20 years with with these turbo cars, only feel safe on the street with vac brakes. Just even a fraction of a second more response time with a manual system for more foot and pedal travel can make the difference between hitting another car or not.

The Powermaster is much too unreliable for me or my family on the street.

Staging at the track is not a function of the power assist if your brakes are in good condition. Just push harder!:smile:

 

[sackracing]

the pedal comes up when the turbo spools up. tried 2 check valves so far, i am gonna put an industrial pneumatic check valve in line and try that.

 

[POWERBRAKEBOB]

Hydroboost Conversion

Vacuum Boosters Need Vacuum. When You Supercharge The Vacuum Booster, It Gives Up. That Is Why We Recommend The Hydroboost. It Runs Off Of The P/s Pump. When The Rpm's Come Up, The P/s Pump Spins Faster, Holding The Hydroboost On Harder. They Build Up To 22 Psi On The Line.

 

[Nick Micale]

We have done MANY vac conversions on 1986-7 turbo Regals over the years and all work great, on the street or strip, when done right.

The check valve in the booster will maintain vac for 2 or 3 pedal applications. Once the pedal is applied and boost builds from vac to pressure, your brakes should be locked and hold as well as manual, or any type assist. The TTA guys prove this in their Pontiacs with a GN engine.:smile:

A hydroboost is a major PIA in an '86-7 GN with its remote fluid reservoir and messy plumbing.

A car that builds launch boost to 22 psi, or anywhere near that, would certainly have a trans brake [and one hell of a loose converter!].:biggrin:

 

[POWERBRAKEBOB]

Hydroboost Conversion

Hi! Well, Everyone Has Installed A Stock Regal Vacuum Booster On A Supercharged Buick V6, Including Ourselves. Vacuum Boosters Need Vacuum, And The Higher Ther More Pressure It Can Push Against The Master. We Have Rebuilt Tens Of Thousands Of Vacuum Boosters In Our 57 Years. We Even Build Them For The Handicapped Guys With Wheel Chairs. The Weight Of Their Hand On The Hand Control Can Stop A 6000lb Van. Great. The V.a. Requires A Vacuum Pump To Go With It, To Supplement The Vacuum Booster(?)s. We Sometimes Add 2 Extra Vacuum Boosters, Truck Style, Downleg Of The Original Booster To Crank Up The Pressure. O.k. Still Requires Vacuum. Vacuum Boosters Are Designed With A Certain Number Of Sq.inches Of Dia. Area. For Example 75 Sq. Inches. So Now, Vac. P.b.'s Are Rated To Operate At 20" Of Engine Vacuum. So 20" Times Those Sq. In. =1500psi Push Against The Master. Now At 10" Times 75 Sq.in = 750psi Push Against The Master.. O.k., Now At 0" Of Vacuum Times 75 Sq Ins. =0 Psi Push Against The Master= Nothing. You Have To Push It All With Your Leg. Turbocharging A Vacuum Booster Will Not Deliver Anty Brake Pressure, Except That Which Your Leg Muscle Can Push. It's Not Enough To Hold This Much Car. It Would Be Like Flying A 747 With A Tiller. Try It. The 747 Uses High Pressure Hydraulics. My Point Is The Hyroboost At Idle Pump Speed Delivers 2000psi To The Calipers With A Firm But Powerful Pedal Feel. It Uses No Vacuum, And No Electricity. The Faster The Pump Spins The Harder The Brakes Will Hold.

 

[GNVAIR]

Hi! Well, Everyone Has Installed A Stock Regal Vacuum Booster On A Supercharged Buick V6, Including Ourselves. Vacuum Boosters Need Vacuum, And The Higher Ther More Pressure It Can Push Against The Master. We Have Rebuilt Tens Of Thousands Of Vacuum Boosters In Our 57 Years. We Even Build Them For The Handicapped Guys With Wheel Chairs. The Weight Of Their Hand On The Hand Control Can Stop A 6000lb Van. Great. The V.a. Requires A Vacuum Pump To Go With It, To Supplement The Vacuum Booster(?)s. We Sometimes Add 2 Extra Vacuum Boosters, Truck Style, Downleg Of The Original Booster To Crank Up The Pressure. O.k. Still Requires Vacuum. Vacuum Boosters Are Designed With A Certain Number Of Sq.inches Of Dia. Area. For Example 75 Sq. Inches. So Now, Vac. P.b.'s Are Rated To Operate At 20" Of Engine Vacuum. So 20" Times Those Sq. In. =1500psi Push Against The Master. Now At 10" Times 75 Sq.in = 750psi Push Against The Master.. O.k., Now At 0" Of Vacuum Times 75 Sq Ins. =0 Psi Push Against The Master= Nothing. You Have To Push It All With Your Leg. Turbocharging A Vacuum Booster Will Not Deliver Anty Brake Pressure, Except That Which Your Leg Muscle Can Push. It's Not Enough To Hold This Much Car. It Would Be Like Flying A 747 With A Tiller. Try It. The 747 Uses High Pressure Hydraulics. My Point Is The Hyroboost At Idle Pump Speed Delivers 2000psi To The Calipers With A Firm But Powerful Pedal Feel. It Uses No Vacuum, And No Electricity. The Faster The Pump Spins The Harder The Brakes Will Hold.

Your posts are getting redundant and tiresome. When properly set up, vacuum works fine. GM did it on the TTA's, the Sy/Ty's and all the super charged 3800's. I would think that they of all people would be concerned about law suits from people having accidents IF they were losing vacuum assist IF there was infact a problem; which ofcourse there isnt.

 

[sackracing]

my vac brakes are not locking in when it goes into boost, the pedal comes back up and it will not even hold 2 lbs. of boost. i have tried 2 new factory style check valves.
is there a trick i am missing?
I need to get a few lbs. of boost on the brakes on the first light before i roll in on the second and get the transbrake.