×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Brake master cylinder question
2

Brake master cylinder question

Brake master cylinder question

(OP)
Have standard tandem brake master cylinder and i plan to convert my braking system to non-ABS.
My question is which port(pipe) provides more volume(pressure) to brake calipers - rear(closest to servo) or front.

RE: Brake master cylinder question

They are hydraulically balanced. Both ports will deliver the same pressure - PROVIDED that the master cylinder does not contain any integral proportioning valves. (most ABS don't have proportioning valves, the ABS hardware serves the same function and more)

As for which one could deliver more volume ... this depends entirely on how much reserve travel is available for the piston inside the master cylinder. It's possible - but unlikely - that this will be different for the circuits that are intended to be for front or rear.

Just maintain the existing layout. Whichever port is connected to front brakes, keep it to front brakes, and whichever is connected to rear brakes, keep it to rear brakes.

You haven't told us what car this is for. Be aware of the possibility that non-ABS versions of your car had additional proportioning valves and the like, in order to get proper front to rear brake balance, which would have been eliminated on ABS-equipped versions. Some have load-sensing proportioning valves on the rear axle in order to get better brake force distribution when carrying a load. Some have diagonally-connected brakes, not front to rear. Some (Volvo) have multiple cylinders in each front brake caliper with some on one circuit and some on the other so that in the event of a hydraulic failure, you still have some braking on both wheels instead of all on one side and none on the other.

RE: Brake master cylinder question

(OP)
Car in question is Alfa 156 mid-engined RWD 3.0V6 using brake servo and MC from Alfa 166(2001year) - 25mm piston size.
AFAIK our ABS use one pipe for FR and RL wheels while other is for RR and FL - but not 100% sure. And that's my concern - if ABS distributes pressure to FR-RL(main pipe) and RR-FL(second pipe) will it make any difference connecting wrongly??

RE: Brake master cylinder question

So they're diagonally connected. The center piston inside the master cylinder is hydraulically balanced so that both circuits get the same pressure, and on a master cylinder for a diagonally-connected system, they will certainly be designed for the same delivery volume of brake fluid. (It HAS to be that way. If it were otherwise, the car would want to veer left or right when braking. With the two circuits balanced, the only way there is any asymmetry is if one circuit fails, and in that situation, one is not concerned about a little effect on the steering, only that somehow in some fashion the car gets stopped ...)

RE: Brake master cylinder question

They are pressure balanced during normal operation. If one circuit loses its fluid and can't develop any pressure, the central piston hits a travel limit stop allowing the other circuit to keep pressure. Dual-circuit master cylinders have been like this since the beginning.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

White Paper – Data Security and Know-How Protection
Our data is constantly exposed to the danger of being intercepted or stolen as it wends its way over global data networks. Data security measures and measures for protecting intellectual property should not, however, first be implemented when data is exchanged – companies must lay the foundation for these measures within their own organization. Download Now
White Paper – Collaboration in the PLM Context
The influence exerted by the Internet of Things (IoT) means that there is a steadily growing need for collaboration in industry. Partners from new industries and areas of application need to be integrated in cross-company business processes to ensure that the lifecycle of smart, connected products can be managed from end to end. Download Now
White Paper – The Challenges of PLM Collaboration
There is cross-company collaboration - and then there is cross-company collaboration. Large-scale corporations and joint ventures need different mechanisms to protect intellectual property from those required for communication between different company locations with heterogeneous IT landscapes. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close