Brake Servo - will UrS6 fit a S2?

[tscheel]

I'm trying to resolve my braking woes, and have tried to find a new brakeservo and possible brake master cylinder. Will the UrS6 servo fit ? It's both LHD cars. What about RHD cars to my LHD S2?

I'd like to think that all hydraulic servos have the same bolt pattern - 7A equipped cars, S2 3B and ABY, RS2 and UrS4/6 20V. But am I right?

And no, I'm not going vacuum - OEM style for me

I've tried to reach Andyg Plym about parts, if you see him - say hello from me

[tscheel]

bump

[UrS4boy]

I'm trying to resolve my braking woes, and have tried to find a new brakeservo and possible brake master cylinder. Will the UrS6 servo fit ? It's both LHD cars. What about RHD cars to my LHD S2? I'd like to think that all hydraulic servos have the same bolt pattern - 7A equipped cars, S2 3B and ABY, RS2 and UrS4/6 20V. But am I right?

The PN for the UrS4/S6 brake servo ("brake booster" in the parts catalogues) is 441612101B. This PN does cross to the ACOQ (coupe quattro and S2 coupe) *BUT* only for the 3B, NM and 7A. The ABY S2s use 8A1612099 for the lhd cars and 894612099A for the rhd AAH, ABC and ABY coupes. These two also cross over to their respective A80Q sedans and avants. The rhd 894162099A also works for the 6A and ACE engined-vehicles in addition to the AAH, ABC and ABY.

The 8A1612099 is also the RS2 brake servo.

So I think the C4 UrS servo does not work on an ABY S2, only the 3B. Why, I do not know. Sorry.

[Error404]

I am sure it will physically work as long as you don't have the run-out style of "big" servo. So I would say if it looks the same it will work.

[SteveH]

Does anyone have any information on the runout larger servo? I presume this option would be better for larger 4-pot/6-pot calipers?

I know of someone with a stack of new servos and they believe they are uprated in some way, perhaps the later servo?

The part number on them is 894612099 A I can take measurements if required.

[Error404]

A bigger servo won't really have much effect other than maybe a slightly lighter pedal I don't think Steve, you want a bigger MC for more "power".

AFAIK the big servo was a LHD only part. Have a look in Tom's RS2 America thread for some pics