Quick question for you early 911S guru's

[Plavan]

What is the new thickness of 1969 911S clutch Disc (Because it's different than normal 911's) (215mm push type clutch)
So what is the new thickness and wear limit. And where did you find the info because we are racking our brains..
Thanks in advance

[jluetjen]

According to the small tech book all of the 69's are the same:
* Installation size and tolerances (mm) of the clutch plate with riveted lining:
- Free thickness (new): 9.8 +/- 0.4 9. Wear limit: 6.5 (when worn evenly)
- Permissible lateral runout: max. 0.6. max 0.6

[silverc4s]

It is definitely thinner. Use the stock disc & the clutch will not disengage!! Don't ask how i know that, right?
I have the info somewhere, I'll try to find it for you.

[silverc4s]

Part Numbers:
With early (67S on) steel/copper faced Pressure Plate #901.116.003.01 use:
901.116.014.00 911S 2.0 up to engine # 6390000

With Alloy Pressure Plate #901.116.009.00 use:
901.116.017.01 911S 2.0 from engine #6390000, HD 914-4, 914-6 all
Still looking for thickness dimension, maybe Warren will show up here soon...;-)

[Plavan]

Thanks guys. The info in Waynes book in the back on clutch tolerances is wrong on the "S". He has the T,E,S having the same clutch disc in 1969 which they did not. It is the same info that jluetjen posted. What??? Porsche makes typos to?
The "S" is thinner to work with the 215mm aluminum pressure plate. I am having a custom/lighter disc made up to work with this light pressure plate but need to know the correct thickness. I would like the clutch to disengage when I put it all together

[silverc4s]

Still have not found dimensions. Here is thickness for the WRONG (Steel Pressure Plate) Disc. This one is TOO THICK and will not work!!

Uncompressed Thickness: 9.8 +/- 0.4mm (0.386 +/- 0.016in)

Wear Limit (Uncompressed) 6.5mm (0.256in) if worn evenly

Max lateral runout is 0.6mm (0.024in)

I think the Alum PP is necessarily thicker, resulting in the thinner disc. Perhaps you can take some measurements and derive the correct thickness by comparing the steel & allot PP to flywheel spacings - if you have access to both...

Still looking, dimensions are not in the factory manuals that I can find - I have all the early manuals here.

[Plavan]

Thanks Silver,
We are running into the same problem. Looking everywhere and not finding it. It's bound to pop up. I'm surprised it has not been talked about before on this board. This is real information people need so they do not make a time consuming mistake.

[silverc4s]

Chad,
Did you buy the PP new? No disc with it?

When I got mine, (Automotion CA, circa 1987) the Pressure Plate & disc came as a set. My wrench, not liking the "looks" of the disc I was going to use, substituted a MUCH BETTER one from his private stock, trying to unsure that I had the best of everything in there.

That's how I learned about this problem.

My point is, I think that these discs may be rare to unobtainable seperately, as they were always sold with a PP and T/O bearing as a kit, back in the day...

[Plavan]

We are having a clutch shop make a disc. Thats why I need the thickness info. I bought these aluminum pressure plates knowing we would have to shave a clutch disc or have a new one made.

[silverc4s]

Have you checked around to the old-line parts houses to see if they have any "thin" (i.e. <5.0 - 7.5mm) 215mm clutch discs, or perhaps look for that part number (017.01) in their old stock??? You could get lucky.

[Plavan]

FYI- I found an actual NOS 1969 911S clutch disc. It measures 7.1mm brand spanking new.

[911pcars]

Chad,
Can you provide the name of the clutch rebuilder? Will want to rebuild mine eventually and would appreciate a reference.

Thanks,
Sherwood

[Plavan]

Unfortunately, with this clutch disc maker the minimum width clutch disc they can make is 8mm. You need to then have the pressure plate taken apart and modified. It turns into a PITA after that.

[silverc4s]

Chad,
Good job! Can you tell us who had the disc? The present owner of my 69 targa may need one before too long.
7.1mm, that's a good number to know. Can you mike the metal disc itself to see if it is thinner than a stock one for us??
Good luck with the racer...;-)

[Plavan]

Jeff at Aase motors in Fullerton had one at his shop. He also had a NOS aluminum pressure plate. I'm not sure if he wants to sell it. He told me he was going to be keeping it for awhile. I'll try to remember to take some pictures and some more measurements when I'm there.