[Walt Fricke]

Here is the deal on Sachs pressure plates for (older) 911s:

2.8 RSR aluminum/aluminum sprayed wear surface: 4 pounds
2.7 stock aluminum housing/cast iron plate: 8 pounds
SC stock cast iron/cast iron: 12 pounds.

I have had the 8 pounder on my SC (and with its original 2.7 motor) since 1984. No problems with idle.

I run the RSR on my track motors. I think the idle (which I have never worked hard at getting just right) could be made smooth enough for the street. And that's with an RSR lightened flywheel. I have had the RSR PPs re-flame sprayed and machined when the wear surface started showing signs of distress.

I suspect the "power" clutch is the 8 pounder.