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Brake pad MM and disc lip

Discussion in 'A3/S3 Forum (8L Chassis)' started by JD09, Jan 30, 2014.

  1. JD09
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    JD09 I'm not modding, I'm improving VCDS Map User

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    [Jan 30, 2014]
    Yes. Very ashamed I'm asking this, as I really should know. Bought some Brembo GT Juniors and have a question re pads and discs.

    Do I presume that I have 3mm of brake pad life on these;

    ImageUploadedByTapatalk1391121157.799462.jpg

    Is that low?

    And is this lip an issue, that I should either get skimmed or replace with new rotors from Bill?

    ImageUploadedByTapatalk1391121192.597880.jpg

    Together with quite rusty rotors...

    ImageUploadedByTapatalk1391121202.483347.jpg
    #1
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  3. Lewis583
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    Lewis583 Active Member VCDS Map User

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    [Jan 30, 2014]
    Yes 3mm is low (though would still pass an MOT (don't get me started on VOSA guidelines)).

    As for the discs they new measuring to be certain with a micrometer and comparing to the minimum thickness. The min thickness is sometimes stamped on the discs somewhere or from technical data. Autodata states min thickness for an S3 is 23mm.
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  4. JimS3
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    JimS3 Active Member

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    [Jan 30, 2014]
    #3
  5. daz-20vt
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    daz-20vt Well-Known Member

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    [Jan 31, 2014]
    These use lcr discs dont they? 323mm x 28mm ? Were talking brakes here mate id replace all of it. Pads and discs. Who knows the life they have had. I bought a 2nd hand set of r32 brakes. Had it all fitted and they were aweful. Changed discs pads and rebuilt the calipers with new seals and they are brilliant brakes on road. Its clear you have your own doubt by the way you asked the question. Why fit any of it to replace parts in a matter of weeks.
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  6. Prawn
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    Prawn My other car is a MINI!!!!

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    [Jan 31, 2014]
    LCR discs should be 28mm thick when new. Minimum thickness is 26mm.

    The easiest way to measure this, is using 2 M8 13mm nuts and a set of calipers.

    Hold a nut on either side of the disc, and measure the total width of the disc and 2 nuts.

    Then measure the thickness of the 2 nuts, and subtract that from your first measurement, and that'll give you a disc thickness not taking into account the lip.

    If you just hold calipers over the disc, you'll be measuring the lip, and not true disc wear.

    a 1mm lip on each side if a fully worn disc.

    From those pics, I'd say the pads, and discs are ready for the bin.
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  7. Lavis89
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    Lavis89 Active Member

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    [Jan 31, 2014]
    Reminds me I need to bin my rear disks, noticeably worn down! Going to feel awesome with new 312 discs up front, new discs back and a can of dot4
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  8. JD09
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    JD09 I'm not modding, I'm improving VCDS Map User

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    [Jan 31, 2014]
    Cheers, Lewis. 28mm I think, but have done what Prawn said and they look pretty lipped/thin.

    Cheers chap, but have DS2500 ready to go on, was just hoping to use the rotors, rather than forking out for more.

    Yeah I've come round to agreeing with you/your train of thought, Daz.

    Clever idea that Prawny, simple too. Done it and works out as roughly 26.5mm so going to bin them as suggested.

    So by reading off here, presume Bill's ecliptic grooved disks are the best bet?
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  9. Lewis583
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    Lewis583 Active Member VCDS Map User

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    [Jan 31, 2014]
    Ahh, my bad. Sorry fella. But, like you are doing, I'd sack them off if it were my car and fit new. :thumbsup:
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  10. JD09
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    JD09 I'm not modding, I'm improving VCDS Map User

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    Yeah I think that's the general consensus! :thumbsup:
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  11. s3dave
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    s3dave TFSI Hybrid

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    [Jan 31, 2014]
    Is it only me... I would have got the last breath out of them,, 3mm pads is only half used lol....
    Maybe sell them to some one for a track day? lasts a few laps??
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  12. JD09
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    JD09 I'm not modding, I'm improving VCDS Map User

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    [Jan 31, 2014]
    Dave in all seriousness, you're welcome to them? Not sure what the pads are, presume the standard ones supplied with the Brembo GT Juniors. Same with the discs. They're both matched to each other, judging by the faces of both?
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  13. s3dave
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    s3dave TFSI Hybrid

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    [Jan 31, 2014]
    Thanks mate, im ok, just done a complete strip down/rebuild of calipers so got all new... was just saying thats all....
    #12
  14. jojo
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    jojo S3 Drift King! Staff Member Moderator

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    [Jan 31, 2014]
    I'd get something out of them prior to replacing personally. They are worn yes, but not dead. Personal preference I guess? Bang them on eBay and get a few beers would be worthwhile.
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  15. Gops
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    Gops 6th gear @7000rpm

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    [Jan 31, 2014]
    Ds3000's!!! Go for them mate!
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