Booster vs dual m/c + balance bar

[element180]

Just wondering for those who know,I found this at the Unbalanced Engineering site...

This kit replaces the stock master cylinder and brake booster with a pair of master cylinders and a balance bar. Brake bias is set by the size of the front and rear master cylinders and balance bar allows rapid and easy changes to the basic brake bias. The kit also multiplies the leverage of the stock pedal to eliminate the need for a brake booster. The kit bolts in the stock location but new brake lines will need to be fabricated.

Would the dual m/c + balance bar be usable for street driving?What I mean is,how much of a difference is there between between the two?

[70 LS1]

Sure you can use the dual master setup for street driving.

A typical braking system uses a tandem master cylinder with equal sized pistons feeding the front and rear brakes. Biasing is usually determined by caliper piston size and/or a proportioning valve.

The advantage to the dual setup is you can adjust your bias based on different master cylinder sizes for the front and rear. And fine tune on the fly for different track conditions with the balance bar. You can use it on the street, too. It can be helpful for custom brake setups.

If you do want a bolt on dual setup, check CNC Brakes. They offer one that they call their street-rod dual setup that is under $300.

[funcars]

I have dual master set-ups on two different cars. Try to start with master cylinder sizes that get the fr/rear balance in the right range to start and then do fine adjustment with the bias bar. You can calculate it based on brake caliper piston sizes, fr/rear weight distribution and rotor diameter. You can find more detail in some of the brake books available. The feel is much better than a vacuum booster on the track.

Good luck with it

[ProTouring442]

Sure you can use the dual master setup for street driving.

If you do want a bolt on dual setup, check CNC Brakes. They offer one that they call their street-rod dual setup that is under $300.

Do you know CNC's web site? I have done some searching, but have had no luck in finding them. Also, does anyone make a dual M/C setup that will work with a booster? Seems this would be a whole lot better than an adjustable "prop-valve" as I understand the latter really only limits rear pressure.

Shiny Side Up!
Bill
'72 442 "Inamorata"

[parsonsj]

Also, does anyone make a dual M/C setup that will work with a booster? Seems this would be a whole lot better than an adjustable "prop-valve" as I understand the latter really only limits rear pressure.

Bill, the balance bar setup doesn't use a prop valve. It uses mechanical leverage to bias the force your foot exerts, so you can adjust the setup to maximize your brakes to the limit of the weakest one.

ATS has played around with boosting bias-bar double masters, but I don't know if they have a viable product yet.

jp

[element180]

Do you know CNC's web site? I have done some searching, but have had no luck in finding them. Also, does anyone make a dual M/C setup that will work with a booster? Seems this would be a whole lot better than an adjustable "prop-valve" as I understand the latter really only limits rear pressure.

Shiny Side Up!
Bill
'72 442 "Inamorata"

http://cncbrakes.com/

[element180]

SERIES 234 Vacuum Assist System
http://cncbrakes.com/cncbrakes.com-a...234&subseries=

SERIES 236 Hydro Assist Assembly
http://cncbrakes.com/cncbrakes.com-a...236&subseries=

[TitoJones]

ATS has played around with boosting bias-bar double masters, but I don't know if they have a viable product yet.

jp

SSSHHhhhhh!!!! That is top secret info, and I have no idea what you are talking about.

Tyler

[parsonsj]

top secret info

Oops ... sorry! I'm thinking I know of a car that might make good use of such a thing ...

jp

[funcars]

I fabbed a dual master balance bar bracket to work with my 1990 corvette power booster and new GN III brakes. It was a PITA and in the end not worth it when the booster failed for the second time (c4 booster are well known for failing). I changed the pedal ratio and went to a manual set-up and it's much better for feel and reliability.

[boodlefoof]

I plan to run a dual manual master cylinder setup on my car when I get to that part of the project.

[SHANE 73Z]

element,

I run the CNC Hotrod (manual) setup in my Camaro. Depending on what kind of pedal ratio & calipers you intend to run, you may run into MC sizing problems.

I am running C4 bore calipers front & rear (real small bores) with a lazy 1.5:1 pedal ratio. With this setup, I am currently running .70" bore Wilwood masters and the pedal is good not great. It has a lot of travel, but is pretty easy to modulate.

These are some of the smallest bore masters I have been able to find.

Take care,
Shane

[ProTouring442]

SSSHHhhhhh!!!! That is top secret info, and I have no idea what you are talking about.

Tyler

Great, something else I need to put on my "need to purchase from ATS" list. Once I get back into a job, I think I'm going to make you guys very happy!


Shiny Side Up!
Bill
'72 442 "Inamorata"

[Elusive R]

I'm running a manual balance bar setup in my Elky and absolutely love it. It takes some getting used jumping from a boosted car into the Elky, but after 5 minutes driving around town, it's really doesn't feel any different. Modulation is fantastic - you can sit right on the edge of lockup very easily.

Ryan