Question Regarding Caliper Piston Alignment

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usury
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The 944na caliper pistons have a "notch" or cutout. The Factory Service Manual says to "adjust piston to 20 degree position" and refers to another page that says "check 20 degree position and adjust with piston turning pliers."

My question is, 20 degree relevant to what?

The photo on that second page in the FSM seems to show something against the bottom side of the fixed portion of the caliper.
PXL_20220929_202452434~2.jpg
PXL_20220929_202452434~2.jpg (1.84 MiB) Viewed 526 times
Is that the reference point for determining 20 degrees?

Also, I'm seeking a single front caliper fixed block...https://www.carpokes.com/viewtopic.php?f=10&t=1108

I made a WTB post in the Garage forum, but I'm new here and I don't know the etiquette yet regarding such requests.

Thank you in advance.
Freelance New Age Renaissance Man
and Wrench Warrior
1987 944na with S2/Turbo facelift
Seattle, Washington, USA

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Tom
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There should be a little recessed step on the face of your piston, which should point toward the leading edge of your rotor as it spins, which is a 20 degree angle relative to the bottom of that piece where the pad slides in. The little wedge piece in the manual is a 20 degree guide tool that you can make out of cardboard, plastic, sheet-metal etc. It should nest into the recessed step part of the piston, which you can kind of see in that picture. It supposed to prevent squealing, with emphasis on "supposed to." ;) The calipers are oriented differently on the old 911's, but here is a pretty good explanation of the concept....

https://www.pelicanparts.com/techarticl ... ebuild.htm

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