Results 1 to 5 of 5

Thread: "S" Calipers central pin removal ??

  1. #1

    "S" Calipers central pin removal ??

    Hi All,
    I'm just about to rebuild a set of Ali 911 "S" calipers I had lying around.
    They had previously (by A Another) stripped blasted and honed.
    Unfortunately they had obviously been left in dubious position as all the pistons are damaged by rust,
    I have tried to buy replacements but that appears impossible or impractical.
    A good friend has supplied some new replacement pistons but without the provision to inset the leakback valve.
    the manufacturing company of the pistons, very reputable and professional, suggested cutting of the central pin in the cantilevers to allow the pistons to be fitted.

    YOUR THOUGHTS PLEASE GUYS.

    Cheers

    Ian

  2. #2
    Senior Member
    Join Date
    Oct 2008
    Location
    Burford, ON, Canada
    Posts
    4,237
    This pistons are almost always rusted due to galvanic corrosion. PMB Performance has everything you need, and may be worthwhile having then remanufacture for you. While some racing S calipers had no pins, there is no real need to remove them. PMB has a couple of piston options that will not require pin removal.
    https://www.pmbperformance.com/lwb-e...11-brakes.html
    https://www.pmbperformance.com/diy-c...ts--acces.html
    Porsche Historian, contact for Kardex & CoA-type Reports
    Addicted since 1975, ESR mbr# 2200 to 2024 03
    Researching Paint codes and Engine Build numbers

  3. #3
    The knockback pins were "state of the art" but are now optional. There are numerous supporters of both their presence and absence.
    If you are still actively racing, these pistons might be of interest.

    Name:  911S-FtCaliperPiston,48x34_04_800x600.jpg
Views: 254
Size:  343.9 KB
    Last edited by JimmyT; 05-28-2020 at 07:31 AM.

  4. #4
    Senior Member
    Join Date
    Aug 2009
    Location
    SF Bay Area
    Posts
    5,557
    Quote Originally Posted by JimmyT View Post
    The knockback pins were "state of the art" but are now optional. There are numerous supporters of both their presence and absence.
    If you are still actively racing, these pistons might be of interest.
    Name:  911S-FtCaliperPiston,48x34_04_800x600.jpg
Views: 254
Size:  343.9 KB
    Hi Jimmy

    Very interesting design of the piston on the right. Does it need to be "clocked" and can it be used with the Knock back devices? I'm assuming these are made from titanium?

    Regards

    Jim

  5. #5
    Yes, they are titanium with DLC coating. It has the provisions for the 'knock-back' device but can also be used without it. It still needs to be clocked during installation. You can see the top surface depression below:
    Name:  911S-FtCaliperPiston,48x34_Annotated.jpg
Views: 234
Size:  303.2 KB

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Message Board Disclaimer and Terms of Use
This is a public forum. Messages posted here can be viewed by the public. The Early 911S Registry is not responsible for messages posted in its online forums, and any message will express the views of the author and not the Early 911S Registry. Use of online forums shall constitute the agreement of the user not to post anything of religious or political content, false and defamatory, inaccurate, abusive, vulgar, hateful, harassing, obscene, profane, sexually oriented, threatening, invasive of a person's privacy, or otherwise to violate the law and the further agreement of the user to be solely responsible for and hold the Early 911S Registry harmless in the event of any claim based on their message. Any viewer who finds a message objectionable should contact us immediately by email. The Early 911S Registry has the ability to remove objectionable messages and we will make every effort to do so, within a reasonable time frame, if we determine that removal is necessary.