1970 911T Pressure Plate?

[Christian]

I am in the process of replacing my pressure plate due to distorted fingers (probably from sitting the last 20 years) and have found a replacement plate. My current pressure plate is aluminium and the replacement I found is cast iron. The type number is the same but the part number is different. Both are Fichels and Sachs. Can I use the cast iron and is the only drawback the added weight of the cast iron? I appreciate any advise from anyone who is more familiar than I. Thanks in advance,
Christian
1970 911T
1963 356 Super

[Wayne 962]

Yes - it's only really a weight difference.

-Wayne

[Jim Sims]

Cast iron pressure plate will cause the moment of inertia of the clutch/flywheel system to increase. Engine will likely idle more smoothly but be slower to rev up and take longer for rev's to fall. Cheers, Jim

[Christian]

Thanks for the advice. I thought that would be the case but of course I was hoping for the easy way out since a friend of mine has a cast iron plate collecting dust. Looks like I'll be looking for an aluminium one instead.
Regards,
Christian

[Wayne 962]

Originally posted by Jim Sims
Cast iron pressure plate will cause the moment of inertia of the clutch/flywheel system to increase. Engine will likely idle more smoothly but be slower to rev up and take longer for rev's to fall. Cheers, Jim

In general, it will make a minimal difference, except when you are revving the engine with the clutch disengaged. Adding the heavier pressure plate is equivalent to adding slightly heavier wheels (rotational elements of the drivetrain).

-Wayne