Gorilla Performance Bal-Bar Balance Bar Dual MC's NO BOOSTER Required
01-10-2011, 04:07 PM
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Gorilla Performance Bal-Bar Balance Bar Dual MC's NO BOOSTER Required
Hello Corvette Owners:
Here is a system for Corvette Owners. Dual Master cylinders and it only takes 16 to 30 square inches in the Engine compartment.
http://www.gorillaperformance.com/
This is in a 1967 Corvette with our juice clutch setup.
Side view
Top view
Inside View 1967 Under Dash
Gorilla Perfomance
Here is a system for Corvette Owners. Dual Master cylinders and it only takes 16 to 30 square inches in the Engine compartment.
http://www.gorillaperformance.com/
This is in a 1967 Corvette with our juice clutch setup.
Side view
Top view
Inside View 1967 Under Dash
Gorilla Perfomance
Last edited by Gorilla Performance; 01-10-2011 at 04:09 PM.
01-10-2011, 09:16 PM
#2
Safety Car
Looks strange. Neat idea. Looks strange.
01-11-2011, 12:50 AM
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Balance Bar Assembly
The Bal-Bar™ system bolts to the stock pedal and uses two (2) 0.75" master cylinders. Each .75" mc has an output pressure of over 1400 psi with a stock pedal. The brackets are designed to fit four (4) different ways and fit most applications with very little modification to the firewall. The best part is it only takes up as little as 16 square inches or a maximum of 30 square inches with the larger master cylinder. The firewall brackets can be mounted together or separately. The Bal-Bar™ can be adjusted manually or with a remote adjuster, no proportional valve required.
Last edited by Gorilla Performance; 01-11-2011 at 01:01 AM.
01-11-2011, 06:36 PM
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Wilwood Balance Bar
Glad you understand the value of the balance bar system.
If you get a chance go to the website and read the brake article on the hotrodsusa website.
MrGorilla
01-11-2011, 10:24 PM
#6
Drifting
Nice package for a racer. You should post this in the Autocrossing section as well. I would think a certain degree of skill would be required to balance the system to preclude swapping ends under moderately hard braking.
01-12-2011, 12:02 PM
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Adjustment of Balance Bar
When I had a shop we built 200 chassis/year all of them with dual master cylinders. Go to the "Tech Section" and view the projects in the right hand column.
The use of a balance bar has been around for years. This product lets you use the stock pedals. On a street car you would only adjust the balance bar on the initial setup. It would be no different than adjusting the balance between the front and rear brake system. You would have to skid the the brakes to see if the rears lock up before the fronts.
1. Most braking systems are already engineered to give you the proper front/rear balance. This is done by using bigger pistons in the front so the clamping force is greater.
Examples: Typical 4 piston front/rear would have 1.75" dia in front and 1.38" dia in the rear. On a drum/drum the factory used larger wheel cylinders in front.
This is way you should try to use the same system front/rear instead of mixing brands, because most people do not understand the principles of braking. For more info on braking systems go to the "Brake Article" on hotrodsusa.com website.
2. A typiclal OEM setup uses distribution or metering block (what some people call a proportional valve) to engineer the balance between front/rear. This is the fine tuning of the balance based on tire size and weight and type of vehicle (2WD vs 4WD). The distribution block for each vehicle if different.
That is why in "The Brake Article" you will see I do not belive in "universal distribution blocks" and all modified cars should use an "adjustable proportional valve". How can you have a universal distribution valve (aftermarket) for a Pickup vs a Lincoln? As you can see each vehicle has different requirements.
When you change "anything" on your factory engineered vehicle you change the engineering. Tires, sway bar, springs, brakes, etc. So your balance between the front and rear should be check and ajusted.
Because most of us have modified the motors with little or no vacuum, boosters will not work. The dual master cylinder system so for this type of application. If you have 18 or more inches of vacuum there is not need to change your system unless you are racing. This is the best of both worlds, stock pedal, 1400psi/master cylinder, compact space in engine compartment, etc.
I could go on and on, but please read "The Brake Article" it can be found by doing a Google search (it comes up first) or going to hotrodsusa website and following the link.
Let me know if you still have questions.
MrGorilla
FYI Here are quotes from "The Brake Article":
"Proportional Valves: Proportional valves are used to regulate the pressure in the line. A proportional valve has an adjustment range of 100 to 1,000 psi. It can decrease your line pressure up to 57 percent. It is generally used on the back brake to adjust the balance between the front and rear brakes.
You NASCAR car fans can relate to over braking by the rear wheels. Remember the drivers on the short tracks that forgot to change the balance bar before ending the pits? Yes, they did spun out."
"Distribution Blocks or Combination Valves: One of the biggest misconceptions is the distribution block or combination valve. Almost every factory car has one. This usually serves as a metering block to adjust the proportioning to the rear brakes, as a "T" fitting for your front left and right front brake lines and brake light warning switch. What people fail to understand is that each car is "engineering" for a specific distribution block based on weight, braking characteristics and tires. So generally most factory cars have different blocks.
Ask yourself this. How can one distribution block be engineered for all applications? So, we have this 23T with tiny tires in front and big tires in the back, we have a 57 Caddy and a 57 Chevy pick up. Do you really think the braking is the same for all three vehicles?"
Here is a picture of a 1950 Chev PU chassis built 1999:
http://www.hotrodheaven.com/tech/cha...pu_brakes4.jpg
1932 Chassis built 1998:
http://www.hotrodheaven.com/tech/cha...32_jerry12.jpg
Picture 2
http://www.hotrodheaven.com/tech/cha.../32_jerry4.jpg
Picture 3
http://www.hotrodheaven.com/tech/cha.../32_jerry5.jpg
Last edited by Gorilla Performance; 02-04-2011 at 01:48 AM.
01-12-2011, 01:31 PM
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"Distribution Blocks or Combination Valves: [COLOR="Blue"] One of the biggest misconceptions is the distribution block or combination valve. Almost every factory car has one. This usually serves as a metering block to adjust the proportioning to the rear brakes, as a "T" fitting for your front left and right front brake lines and brake light warning switch. What people fail to understand is that each car is "engineering" for a specific distribution block based on weight, braking characteristics and tires. So generally most factory cars have different blocks.
A distribution block has no valving functions of any kind, and only serves to contain the differential pressure warning switch; one can serve many different applications, as it has no influence on the hydraulic system operation. They were used on Corvettes from '67-'77.
A combination valve contains the distribution function with the differential pressure warning switch, a metering/hold-off valve for the front calipers on a disc/drum system, and a proportioning valve for the rear drum or disc system. Combination valves must be calibrated/specified uniquely for each individual application, and were used on Corvettes starting in 1978.
Photos below show a typical distribution block, and a typical combination valve; they're completely different.
01-12-2011, 01:45 PM
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Distribution blocks and combination valves are two completely different animals, and serve completely different functions; they shouldn't be confused with each other, or mentioned in the same sentence.
A distribution block has no valving functions of any kind, and only serves to contain the differential pressure warning switch; one can serve many different applications, as it has no influence on the hydraulic system operation. They were used on Corvettes from '67-'77.
A distribution block has no valving functions of any kind, and only serves to contain the differential pressure warning switch; one can serve many different applications, as it has no influence on the hydraulic system operation. They were used on Corvettes from '67-'77.
I.E. 3/16" inlet and 1/8" outlet the only way to tell for sure is to take a "numbered drill bit" and check to see if the inlet passage way is the same as the outlet passage way.
The Corvette might be the exception on porting size, because it had disc/disc engineered from the factory on all their models and did not offer a disc/drum vs drum/drum. And that is why there is so much confusion.
MrGorilla
"What people fail to understand is that each car is "engineering" for a specific distribution block based on weight, braking characteristics and tires. So generally most factory cars have different blocks."
Last edited by Gorilla Performance; 01-13-2011 at 12:12 PM.
01-15-2011, 01:41 PM
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Firewall Room and Pressure
I have had several emails regarding the recess area of the mid-year firewall. Our firewall bracket fits in this recess. The only modification to your firewall is filling in the stock master cylinder hole and drilling out the new holes for our bracket.
Here is the additional info on pressure.
MrGorilla
Here is the additional info on pressure.
The advantage of the Dual Master cylinder is with a 3/4" bore the output pressure is 1400 psi and there is no wasted energy when using a balance bar. This is a copy of a link from the Brake Article on the internet and I quote (Dual MC's):
........."There are major advantages to using dual master cylinders: (1) Smaller diameter master cylinders can be used to increase output pressure. The design allows the application of two master cylinders being applied at the same, thereby doubling the volume output. Because of this high pressure output you will not need a vacuum booster. If you are running any type of camshaft, chances are you do not have enough vacuum to run the booster anyway. (2) The balance bar eliminates the use of a proportional valve and gives you the optional remote adjustment. (3) The remote fill applications deletes the need for residual valve normally used when the reservoirs are lower than the calipers.
When calculating the output pressure of each master cylinder you can not say that applied pressure is “shared” equally between the two (2) master cylinders. If the two master cylinders did not have a balance bar between them and the application of force was always equally distributed this statement would be true. The balance bar allows the applied pressure to be distributed unequally.
Example:
6:1 ratio pedal assembly
¾" master cylinders
Applied force of 100 pounds with your foot
The formula shows that this combination produces 1359 psi, however if you apply the 100 pounds of force to both of them equally it will only produce 50 percent or 679.5 psi.
What the balance bar allows you to do is apply 65% of the force to the front and 35% to the rear so the actual output pressures would be 883 & 475 psi.
This is how you are able to obtain maximum braking with the same amount of applied force. When you are using a tandem master cylinder (OEM type inline bore) the output pressure is equal in both ports and the only way to reduce the pressure to the rear braking system is through metering (distribution block, combination valve or engineering in the master cylinder) or proportional valve. This works fine when you have more than enough pressure with a power booster but when you are using a manual master cylinder this energy is “wasted”.
The easiest way to test this "wasted energy" is to apply 100 uniform pounds of pressure to a 6:1 pedal ratio and measure the pressure at the front calipers and the rear calipers with a pressure gauge. You will find that you will not have 763 psi you will have a reduced amount directly related to your proportioning or reduced pressure in the rear. If you reduce the pressure in the rear by 15% the out pressure in the front system will only have 648 psi at the gauge.
The only way to know the effective actual output pressure of your system (Tandem MC OEM type) with a proportional valve or distribution block installed is to measure it with a pressure gauge. The only disadvantage is higher cost..... but what is your car worth? What is your life worth?
This setup is not for everybody, it is only another solution to no or little vacuum on the muscle cars we are building today. We did not have the horse power or speed 10, 20 or 30 years ago, so we did not need as much braking as we do now. With today's technology the sky is the limit and the only thing holding us from going faster is the tires, suspension and brakes not so much the engines. Band-aids like hydro-booster and vacuum canister/pumps are just one more thing to go wrong.
........."There are major advantages to using dual master cylinders: (1) Smaller diameter master cylinders can be used to increase output pressure. The design allows the application of two master cylinders being applied at the same, thereby doubling the volume output. Because of this high pressure output you will not need a vacuum booster. If you are running any type of camshaft, chances are you do not have enough vacuum to run the booster anyway. (2) The balance bar eliminates the use of a proportional valve and gives you the optional remote adjustment. (3) The remote fill applications deletes the need for residual valve normally used when the reservoirs are lower than the calipers.
When calculating the output pressure of each master cylinder you can not say that applied pressure is “shared” equally between the two (2) master cylinders. If the two master cylinders did not have a balance bar between them and the application of force was always equally distributed this statement would be true. The balance bar allows the applied pressure to be distributed unequally.
Example:
6:1 ratio pedal assembly
¾" master cylinders
Applied force of 100 pounds with your foot
The formula shows that this combination produces 1359 psi, however if you apply the 100 pounds of force to both of them equally it will only produce 50 percent or 679.5 psi.
What the balance bar allows you to do is apply 65% of the force to the front and 35% to the rear so the actual output pressures would be 883 & 475 psi.
This is how you are able to obtain maximum braking with the same amount of applied force. When you are using a tandem master cylinder (OEM type inline bore) the output pressure is equal in both ports and the only way to reduce the pressure to the rear braking system is through metering (distribution block, combination valve or engineering in the master cylinder) or proportional valve. This works fine when you have more than enough pressure with a power booster but when you are using a manual master cylinder this energy is “wasted”.
The easiest way to test this "wasted energy" is to apply 100 uniform pounds of pressure to a 6:1 pedal ratio and measure the pressure at the front calipers and the rear calipers with a pressure gauge. You will find that you will not have 763 psi you will have a reduced amount directly related to your proportioning or reduced pressure in the rear. If you reduce the pressure in the rear by 15% the out pressure in the front system will only have 648 psi at the gauge.
The only way to know the effective actual output pressure of your system (Tandem MC OEM type) with a proportional valve or distribution block installed is to measure it with a pressure gauge. The only disadvantage is higher cost..... but what is your car worth? What is your life worth?
This setup is not for everybody, it is only another solution to no or little vacuum on the muscle cars we are building today. We did not have the horse power or speed 10, 20 or 30 years ago, so we did not need as much braking as we do now. With today's technology the sky is the limit and the only thing holding us from going faster is the tires, suspension and brakes not so much the engines. Band-aids like hydro-booster and vacuum canister/pumps are just one more thing to go wrong.
01-15-2011, 06:59 PM
#11
Safety Car
John Z. is spot on about the 67-76 Corvette distribution block. It only has a differntial pressure switch that turns on the "BRAKE" light if hydraulic pressure on one side or the other gets weak or fails. Hydraulic proportioning in these cars (and in all pre 67 cars with single circuit master cylinders) used only caliper piston or wheel cylinder cup diameters selected to get the correct braking force at the front and rear wheels.
Not making any comments about the Bal Bar system, which looks like a good choice to substitute power brakes, this is just an FYI. What you didn't mention to the readers is that to get lower pedal effort you have to cut down on the cross-sectional area of the master cylinder pistons compared to a stock master cylinder. The amount of pedal travel to get the same hydraulic pressure will increase in proportion to the reduction in piston cross-section area. Some users may not know what to expect and may be unnerved by any increase in pedal travel.
Not making any comments about the Bal Bar system, which looks like a good choice to substitute power brakes, this is just an FYI. What you didn't mention to the readers is that to get lower pedal effort you have to cut down on the cross-sectional area of the master cylinder pistons compared to a stock master cylinder. The amount of pedal travel to get the same hydraulic pressure will increase in proportion to the reduction in piston cross-section area. Some users may not know what to expect and may be unnerved by any increase in pedal travel.
01-16-2011, 11:38 AM
#13
Safety Car
I am starting my second go around at this time! 
01-16-2011, 12:05 PM
#14
Melting Slicks
Let me start by saying that I have manual brakes in both my 63 Corvette and my Cobra replica. The Cobra has a balance bar setup and it works well. Having said that, I'd like to add these comments about brake pedal force. Unless you have some boosting system, the simple truth is that the force applied to the pedal multiplied by the distance traveled by the pedal equals the force applied to the brake pistons multiplied by the distance traveled by the pistons. It doesn't matter what combination of levers, master cylinders, tubing sizes and wheel cylinders you have in between the pedal and wheel cylinder pistons, the fundamental relationship between pedal movement and wheel piston movement remains the same. So, replacing power brakes with manual brakes while leaving the pedal throw and wheel cylinder piston size unchanged will increase the amount of pedal force required to achieve the same level of braking action.
01-16-2011, 02:32 PM
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John Z. is spot on about the 67-76 Corvette distribution block. It only has a differntial pressure switch that turns on the "BRAKE" light if hydraulic pressure on one side or the other gets weak or fails. Hydraulic proportioning in these cars (and in all pre 67 cars with single circuit master cylinders) used only caliper piston or wheel cylinder cup diameters selected to get the correct braking force at the front and rear wheels.
Not making any comments about the Bal Bar system, which looks like a good choice to substitute power brakes, this is just an FYI. What you didn't mention to the readers is that to get lower pedal effort you have to cut down on the cross-sectional area of the master cylinder pistons compared to a stock master cylinder. The amount of pedal travel to get the same hydraulic pressure will increase in proportion to the reduction in piston cross-section area. Some users may not know what to expect and may be unnerved by any increase in pedal travel.
Unless you have driven a car with dual master cylinder it is difficult to explain the performance of this set up. If you were correct they would not be using this set in race cars. It would be impossible to "heel to toe".
MrGorilla
01-16-2011, 02:54 PM
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Let me start by saying that I have manual brakes in both my 63 Corvette and my Cobra replica. The Cobra has a balance bar setup and it works well. Having said that, I'd like to add these comments about brake pedal force. Unless you have some boosting system, the simple truth is that the force applied to the pedal multiplied by the distance traveled by the pedal equals the force applied to the brake pistons multiplied by the distance traveled by the pistons. It doesn't matter what combination of levers, master cylinders, tubing sizes and wheel cylinders you have in between the pedal and wheel cylinder pistons, the fundamental relationship between pedal movement and wheel piston movement remains the same. [COLOR="DarkSlateGray"]So, replacing power brakes with manual brakes while leaving the pedal throw and wheel cylinder piston size unchanged will increase the amount of pedal force required to achieve the same level of braking action.[/COLOR
I.E. (In Example): If you have a 1" master cylinder the area equals 1/2" x 1/2" x 3.14 = 0.785 Square Inches. So, 100 pounds (of applied foot pressure) X 6 (pedal ratio) divided by 0.785 = 764 pounds of pressure.
If you have a 1-1/8" master cylinder, 100 psi X 6 (pedal ratio) divided by 0.9935 = 604 pounds of pressure.
Here is some info on master cylinder with "constant" of 6 to 1 pedal ratio and 100 psi being applied.
3/4" master cylinder = 1359 psi
13/16" master cylinder = 1158 psi
7/8" master cylinder = 998 psi
15/16" master cylinder = 870 psi
1" master cylinder = 764 psi
1-1/8" master cylinder = 603 psi
If you have a 1-1/8" master cylinder, 100 psi X 6 (pedal ratio) divided by 0.9935 = 604 pounds of pressure.
Here is some info on master cylinder with "constant" of 6 to 1 pedal ratio and 100 psi being applied.
3/4" master cylinder = 1359 psi
13/16" master cylinder = 1158 psi
7/8" master cylinder = 998 psi
15/16" master cylinder = 870 psi
1" master cylinder = 764 psi
1-1/8" master cylinder = 603 psi
For those of you not able to read "The Brake Article", here is some additional information as shown on this page:
http://www.deanoshiro.com/brakes/bra...le.html#dualmc
There are major advantages to using dual master cylinders: (1) Smaller diameter master cylinders can be used to increase output pressure. The design allows the application of two master cylinders being applied at the same, thereby doubling the volume output. Because of this high pressure output you will not need a vacuum booster. If you are running any type of camshaft, chances are you do not have enough vacuum to run the booster anyway. (2) The balance bar eliminates the use of a proportional valve and gives you the optional remote adjustment. (3) The remote fill applications deletes the need for residual valve normally used when the reservoirs are lower than the calipers.
When calculating the output pressure of each master cylinder you can not say that applied pressure is “shared” equally between the two (2) master cylinders. If the two master cylinders did not have a balance bar between them and the application of force was always equally distributed this statement would be true. The balance bar allows the applied pressure to be distributed unequally.
Example:
6:1 ratio pedal assembly
¾" master cylinders
Applied force of 100 pounds with your foot
The formula shows that this combination produces 1359 psi, however if you apply the 100 pounds of force to both of them equally it will only produce 50 percent or 679.5 psi.
What the balance bar allows you to do is apply 65% of the force to the front and 35% to the rear so the actual output pressures would be 883 & 475 psi.
http://www.deanoshiro.com/brakes/bra...le.html#dualmc
There are major advantages to using dual master cylinders: (1) Smaller diameter master cylinders can be used to increase output pressure. The design allows the application of two master cylinders being applied at the same, thereby doubling the volume output. Because of this high pressure output you will not need a vacuum booster. If you are running any type of camshaft, chances are you do not have enough vacuum to run the booster anyway. (2) The balance bar eliminates the use of a proportional valve and gives you the optional remote adjustment. (3) The remote fill applications deletes the need for residual valve normally used when the reservoirs are lower than the calipers.
When calculating the output pressure of each master cylinder you can not say that applied pressure is “shared” equally between the two (2) master cylinders. If the two master cylinders did not have a balance bar between them and the application of force was always equally distributed this statement would be true. The balance bar allows the applied pressure to be distributed unequally.
Example:
6:1 ratio pedal assembly
¾" master cylinders
Applied force of 100 pounds with your foot
The formula shows that this combination produces 1359 psi, however if you apply the 100 pounds of force to both of them equally it will only produce 50 percent or 679.5 psi.
What the balance bar allows you to do is apply 65% of the force to the front and 35% to the rear so the actual output pressures would be 883 & 475 psi.
MrGorilla
Last edited by Gorilla Performance; 01-17-2011 at 10:39 AM.
01-16-2011, 03:12 PM
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The Brake Article
This link will help you.
http://www.deanoshiro.com/brakes/brakearticle.html
Please don't be discouraged, This was written in 1994, it has been read and copied by thousands of people and other companies. A good portion of our customers are engineers, you are either right or wrong with an engineer. They like a black or white answer.
MrGorilla
Last edited by Gorilla Performance; 01-16-2011 at 04:13 PM.
01-16-2011, 03:26 PM
#19
Le Mans Master
How does using the balance bar change the "feel" as opposed to using a '70s Corvette dual cylinder M/C with a separate proportioning valve to the rears? I assume this has an effect in the way the "knee-point" works.
I run manual front '77 disks and rear '64 drums with a 10# residual valve and Tilton 7-position proportioning valve for the rears. The proportioning valve is mounted under the dash.
Thanks
I run manual front '77 disks and rear '64 drums with a 10# residual valve and Tilton 7-position proportioning valve for the rears. The proportioning valve is mounted under the dash.
Thanks
Last edited by toddalin; 01-16-2011 at 03:30 PM.
01-16-2011, 03:50 PM
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How does using the balance bar change the "feel" as opposed to using a '70s Corvette dual cylinder M/C with a separate proportioning valve to the rears? I assume this has an effect in the way the "knee-point" works.
I run manual front '77 disks and rear '64 drums with a 10# residual valve and Tilton proportioning valve for the rears.
Thanks
I run manual front '77 disks and rear '64 drums with a 10# residual valve and Tilton proportioning valve for the rears.
Thanks
Would depend on where you adjust the balance bar. If you have it at 65/35 the pressure comparison would be 883 vs 764 with a 1" manual (OEM type) or it would 764 divided by 883 = 86.52%, which means there would be about 14% less effort vs the 1" you are currently using.
(That with the assumption you have a 1" manual mc now)
Rotors lock up would happen between 900 and 1,200 psi that would depend on the caliper pad compound, rotor diameter, rotor temp, caliper pad area and caliper piston size just to name a few.
With all of these factors being the same and you have the dual mc vs 1" OEM type. To produce that 1,000 psi at the rotor you would have to push down on the pedal:
130 pounds with your foot using a 1" OEM type
and
113 pounds with you foot using a 3/4" dual and the balance bar set at 65/35.
The amount of foot pressure a person can push would be based on his size and weight. It would be easier for a 280 pound person to push the extra force required vs a 130 pound person. When you "heel to toe" your car in a corner it becomes more difficult.
MrGorilla