Re: Brake master cylinder research

[Sachelle Babbar <sbabbar@iris.nyit.edu>]

What are the details of the larger rear brake setup on wagons? How was it
ordered from th factory? Do they offer any appreciable stopping power over
the regulars in sedans?



****************************************************************************
*Steve                                       Sachelle Babbar
*'84  5ksT 1.6-2.0 bar                    <SBABBAR@IRIS.NYIT.EDU>
*Cockpit adjustable wastegate, AudiSport badge
*
*Disclaimer:"Any information contained herein is based purely on my own
*personal experience and may not necessarily reflect yours. Use caution as
*your results may vary from mine."
********************************************************************************

On Thu, 30 Apr 1998, Lawson, Dave wrote:

> Reviewing the archives, the following information was presented for
> 4000/5000 master cylinders
> 
> >>
>  
>  '79-'83 non-turbo-----22mm bore----431-611-019G
>  '80-'81 turbo-----------23mm bore----437-611-019A
>  '82-'83 turbo-----------22mm bore----437-611-019B
>  '84-'88 all---------------23mm bore-----443-611-021
> 
> Naturally there's a disclaimer to this...there's another option for some
> '86-88 wagons only...447-611-021 with the 25mm bore....that would cover
> the
> rare larger rear caliper optioned wagons.
> 
> 
> Part no.  v              Year    v               mm      v
> 
> 431 611 019 K      '78-'81 5000..................22.2mm
> 
> 437 611 019 A      '80-'81 5000 turbo.........23.81mm.
> 
> 437 611 019 B      '82-'83 5000 turbo.........22.2mm.
> 
> 813 611 019        8/ '80-'84 4000 (coupe 81-84)..........20.64mm.
> 
> 443 611 021       quattro 8/82-85; 5k '84-'88; 5kq '87-'88; 5kt '84-'88;
>                           5ktq 86-88....................23.81mm.
> 
> >>
> 
> I was looking over a few microfiches and found the following data
> 
> Early ur-q  23.81mm x 19/17
> Late ur-q   25.4mm x 18/18
> 
> And for the RS2  25.40mm x 13/22.5
> 
> The 200 had similar listings, but I didn't write those down.
> 
> We know the diameter of the master cylinder is the first number, but
> what I was wondering is what the 19/17 means?
> Is it some kind of stroke length for the front and rear parts of the
> tandem master cylinder setup?
> 
> thanks
> -
> Dave Lawson
> 
>