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Morph914
Today I was installing my new PMB rotors and calipers, but it seems I took 1 step forward and 2 back. I purchased the late 5 lug conversion kit from PMB and I believe I received the wrong front rotors. headbang.gif
After installing the rotors, I went to install the calipers and they did not line up. After doing some investigative work I discovered that my old rotors are a bit different, the hat is taller and the inside oil seal surface is recessed about a 1/4” where the new one seems to be flush with the rotor surface.
I’ll have to wait until Monday to sort this out with Eric.
Click to view attachment Click to view attachment Click to view attachment
bdstone914
What year us your car? The rotors change in 72 at vin 19033. Why is there an inner bearing race on the rotor by the spindle nut.
Literati914
There are three different hub thicknesses... did PMB understand which ones you have?


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Cairo94507
Great catch Bruce. beerchug.gif
Morph914
QUOTE(bdstone914 @ Aug 15 2020, 01:44 PM) *

What year us your car? The rotors change in 72 at vin 19033. Why is there an inner bearing race on the rotor by the spindle nut.


It’s a ‘74, and I’m not sure what you are talking about as far as the inner race inside of the spindle nut. There is an outer race a bearing, thrust washer and nut. I think what you might be seeing is the shiny machined hub that the cap fits onto.

Cheers,
John
Morph914
QUOTE(Literati914 @ Aug 15 2020, 02:46 PM) *

There are three different hub thicknesses... did PMB understand which ones you have?


I did not realize there were more than early and late, so I just ordered the late.

John
davep
QUOTE(Literati914 @ Aug 15 2020, 12:46 PM) *

There are three different hub thicknesses.

I am aware of two, can you define all three please.
Literati914
QUOTE(davep @ Aug 16 2020, 03:16 PM) *

QUOTE(Literati914 @ Aug 15 2020, 12:46 PM) *

There are three different hub thicknesses.

I am aware of two, can you define all three please.


@davep

Yep, here they are - I can not varify that the corresponding numbers are correct to the pictured hubs. That's kind of my problem .. as I have Bembo Aluminum calipers from an Alfa and I can not figure which of these are needed - and hub sellers are all over the place with info and/or lack of.
IPB Image

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davep
Okay, I see the problem. You are referring to 911/912/914-6 hubs onto which a brake rotor is mounted.
The OP has a 914/4 strut with brake rotors that act as their own hubs; that is, the bearings are mounted within the brake rotor as opposed to being within the hub. So, completely different systems.
The rotor in the first post appears to be an early type (not hub centric), so not appropriate for a later strut and caliper; the offset is different so that is why the caliper will not centre on the rotor.
dr914@autoatlanta.com
looks like you have an early rotor mounted that would be the problem

QUOTE(Morph914 @ Aug 15 2020, 03:59 PM) *

QUOTE(bdstone914 @ Aug 15 2020, 01:44 PM) *

What year us your car? The rotors change in 72 at vin 19033. Why is there an inner bearing race on the rotor by the spindle nut.


It’s a ‘74, and I’m not sure what you are talking about as far as the inner race inside of the spindle nut. There is an outer race a bearing, thrust washer and nut. I think what you might be seeing is the shiny machined hub that the cap fits onto.

Cheers,
John

Literati914
QUOTE(davep @ Aug 17 2020, 09:34 AM) *

Okay, I see the problem. You are referring to 911/912/914-6 hubs onto which a brake rotor is mounted.
The OP has a 914/4 strut with brake rotors that act as their own hubs; that is, the bearings are mounted within the brake rotor as opposed to being within the hub. So, completely different systems.
The rotor in the first post appears to be an early type (not hub centric), so not appropriate for a later strut and caliper; the offset is different so that is why the caliper will not centre on the rotor.


Of course you are right.. I don't know why I assumed 911 struts. I honestly didn't see the extra holes - and btw, why are there only 2 extra holes? .. usually there'd be 3 unused holes, no? maybe not 5/130 ?
davep
Absolutely 3 unused holes; the one on the left is hidden behind the stud.
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