Best valve stem seals?

[68keyblr]

I'm rebuilding the GT-40Ps and would like some input on which type of Valve Stem Seals I should get. I want the best seal possible. This is a for a Daily Driver with occasional blasts to 6K rpm.

There are rubber, viton, teflon, viton rubber, nitrile rubber, and who knows what else...

So which is best for my application?

 

[TenorPlayinGuy]

I would go with the viton rubber.

Teflon seems to work well as well but in my experience is a race accessory.