Spec for S aluminum pressure plate?

Shaun @ Tru6 · 01-28-2009, 01:49 PM

I'm parting out a 67 Normal motor and it has an aluminum pressure plate. there is a shallow (thousanths) step in the surface, but both inner and outer bevels are prominent.

It certainly looks like a usable component when resurfaced, or perhaps as is.

Is there a spec I can follow to determine how much life has been put on it? how much life it has left?

Plavan · Plavan's Garage

Is it copper faced or grey metallic? Probably still good if it does not have any scoring... The copper faced units are junk.

Shaun @ Tru6 · 01-28-2009, 05:38 PM

it's grey metallic Chad, and no scoring. will try to take a pic after I wash the case.

What are the quick specs on your ST motor BTW?

Shaun @ Tru6 · 01-29-2009, 05:40 AM

pics

djpateman · 01-29-2009, 06:15 AM

That looks like the 69S aluminum PP that requires the thinner friction disk. I believe the friction surface of the PP is steel faced, but I'd like to learn more myself. I have one almost new PP and 3 disks to go with it that i am saving for a project.

Plavan · Plavan's Garage

Yep that looks like a 69S plate. Still looks good to me. As DJ states you will need a thinner clutch disc that are hard to find (not racing worthy if you plan on racing). If you were to install that PP with a normal 911 clutch disc it would never disengage.

Here is a previous thread on modifications I did to my aluminum pressure plate. I'm still running it without any failures.

What do you guys think of this? I am testing it next weekend.

djpateman · 01-29-2009, 06:40 AM

Chad, what exactly were the modifications to the PP? It still looks very stock at first glance.

Plavan · Plavan's Garage

I took it apart and machined 1mm off of the back side so I could use a custom light8mm racing clutch disc. I also had the springs heat treated for more clamping force. It would slip on my race car if I did not heat treat the springs.

Shaun @ Tru6 · 01-29-2009, 07:26 AM

any idea on value matched with a good disc (need to 100% confirm)? want to put it up for sale with a reasonable price.

Plavan · Plavan's Garage

Hi Shaun,
No idea on a package deal. I bought one of those PP NOS for $250 without a clutch disc, but then did my mods to it. The stock "thin" disc would not hold up to racing, its actually white in color too if I remember correctly.
I have two of the Copper faced units, but I cant recommend those because they are junk, there is a reason Porsche went to the type you and I have. They hold up much better.

Shaun @ Tru6 · 01-29-2009, 07:56 AM

thanks Chad. I'll see if I can get $200 for it.