Ur-quattro brake question

[Bryan Gunn <bgunn@voicetek.com>]

Hi folks,

Has anyone ever installed the 25mm master cylinder (447 611 021) on the 
stock ur-q (with single piston calipers) brake servo?

For those of you in the UK ans elsewhere, did Audi change the brake servo
and/or hydraulic pump when they installed the dual piston calipers in '87?

I have what I think is the 25mm master cylinder, but I bought it used through
mail order, so I don't know what they actually sent me. This master cylinder
is a couple mm too large where it fits into the brake servo. Do I have the
wrong master cylinder, or does 447 611 021 not fit the ur-quattro brake
servo?

Thanks,
-- 
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*            Bryan Gunn                  Email: bgunn@voicetek.com           * 
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