mgs
[Top] [All Lists]

Re: [Mgs] MGB rear brakes

To: MG List <mgs@autox.team.net>
Subject: Re: [Mgs] MGB rear brakes
From: Max Heim <max_heim@sbcglobal.net>
Date: Tue, 24 Feb 2009 10:55:30 -0800
on 2/24/09 10:11 AM, Simon Matthews at simon.d.matthews@gmail.com wrote:

> Max,
> 
> It's not quite so simple. This description of dual master cylinders
> describes a balance bar used to ensure equal force is applied to each
> cylinder:
> http://www.hotrodheaven.com/tech/brakes/brakes3.htm
> In this scenario, the balance bar would act to equalise the pressures
> between front and rear. Also, are not some brake systems split
> diagonally?

Balance bars are used in race cars (which are invariably disc/disc). I was
talking about tandem dual MCs as used in almost all production cars.

While I have heard of diagonally-split systems in theory, I cannot think of
a single real-world application. I am sure someone will speak up and
enlighten me.

> 
> This patent describes a tandem dual-master cylinder setup in which the
> two circuits also have equal pressure:
> 
> http://www.tpub.com/content/construction/14273/css/14273_248.htm

I can't tell from this fragment how this applies to the argument, if at all.

Anyway, I am not just arguing from a theoretical standpoint, here -- I am
describing reported real world experiences with examples of applications.
You can say what you want, but there seems to be a generally-held belief
that using larger diameter rear wheel cylinders on tandem MC disc/drum brake
systems has the effect of reducing rear wheel lock-up, particularly for
vehicles with strong front weight bias.



> Regards,
> Simon
> 
> 
> On Tue, Feb 24, 2009 at 9:31 AM, Max Heim <max_heim@sbcglobal.net> wrote:
>> But in a dual master cylinder system, it is possible to meet resistance in
>> one circuit before reaching that point in the other circuit (for example, in
>> the case of a failed hose in one circuit). The pressure does NOT equalize
>> between the completely independent circuits. So my argument is that by using
>> larger wheel cylinders in the rear brake circuit, you are delaying the onset
>> of braking force in the rear circuit, by requiring more fluid to be moved in
>> order to reach the point of applying braking force RELATIVE TO THE FRONT
>> CIRCUIT. Now do you see what I mean?
>> 
>> I think we have established that single and dual master cylinder systems
>> behave very differently in this respect, so that one needs to be careful in
>> defining the question.
>> 
>> --
>> 
>> Max Heim
>> '66 MGB GHN3L76149
>> If you're near Mountain View, CA,
>> it's the primer red one with chrome wires
>> 

--

Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the primer red one with chrome wires
_______________________________________________
Support Team.Net  http://www.team.net/donate.html




Mgs@autox.team.net
http://autox.team.net/mailman/listinfo/mgs

http://www.team.net/archive

<Prev in Thread] Current Thread [Next in Thread>