3.2 Valve Stem Seals

[1972_911T]

Im just about the rebuild the heads on my 3.2 im just waiting for them to come back from having the new guides fitted, what im wanting to know is should I stick with the standard stem seals that came as part of my victor reinz top end set or is there a better alternative thats worth while?

Steve

[Henry Schmidt]

New style brown valve stem seals are probably Viton and are great quality but we only use white Teflon seals. I was just speaking to someone about this very topic and my conclusion was that I am "old school" and kind of stuck in the world of what has worked for me. I will say that proper installation of Teflon seals is easier.
In short, use what you are comfortable with.

Porsche used Teflon from 63-83 and Viton from 84 until now.

[Eagledriver]

And SC motors have a reputation for long life whereas the 3.2 has a reputation for premature valve guide wear. Coicidence? You be the judge.

-Andy

[Henry Schmidt]

You know in all these years I never noticed that.
What I have noticed is that the 2.7 had the worst valve guide wear of any Porsche engine (I saw them unusable at 35,000 miles and I've seen them so worn that they start to mushroom) and they had Teflon seals.
Perhaps it's not all that cut and dried.

An additional thought. Valve guide wear is a function of heat, lubrication, product material and valve stem diameter to guide length ratio.
I wonder if the new engines have small diameter stems in an attempt to improve that ratio.
We know it improves air flow across the valve but was Porsche also thinking valve guide wear.