Valve stem seal preferences?

[Jack21]

Heads on motor are TFS Twisted Wedge aluminum.

When assembling the heads, TFS specified using viton rubber seals. Their rationale was that the valve guides needed the extra oil to properly lube the valves and guides. If this were true, then any canted valve engine would have the same issue.

Even my grocery getter rebuilds get teflon insert seals (Perfect Circle), if not all teflon (Crane).

The machinist thought I was crazy for not using teflon, but installed the viton seals. Should I have listened to my own (and my machinists) instincts? Use teflon, not rubber?

Since new, motor has used about a quart of oil per 1,000 miles, and it shouldn't be using any.

What valve guide seals are you using on TFS heads, viton, or teflon? Anybody using teflon having any valve guide wear problems? Anybody using viton having any oil consumption problems?

Engine has a little over 14,000 miles on it so it should be broken in. Used 10W30 to break it in for 3,000, miles, then Castrol synthetic.

[Hotfingrs]

I use the teflon seals.....rubber gets hot and hard and cracks and breaks down...and the pieces are in the engine then....

[Wade Chamberlain]

8000 miles on my box-stock Twisted Wedge heads, and not burning a drop of oil. The TW heads typically require non-stock length pushrods to get the valvetrain geometry dialed in. If the geometry is wrong, the guides will wear in a hurry.

[Double Venom]

Duuuhhh???
Don! Hey Don, answer Jacks question will ya?
DV...out in never - never land right now

[Jack21]

Thanks Wade. Burtonsville Performance Machine in Burtonsville MD did the machine work, and trial assembly. MY TFS's, also box stock did require special length pushrods which were measured, ordered from Crane, and installed. Did you use the TFS box stock viton valve stem seals, or did you replace them with teflon seals? Thanks.

[Satanpez]

I don't know much about performance cars...

But I'm changing the valve stem seals on my Mustang which has 33,000 original miles. Yeap, that's right, they're hard and brittle at 33,000 miles. If I knew I could buy something besides rubber I'd sure as hell be using it.

Rubber definately gets hard and brittle.

-steve in nj-

[Scufty]

well you can Satn I do believe ..Teflon that push right over your guide to hold them down

[lineslinger]

Jack21,
You should listen to your machinist, he does it for a living.
Especially for something like a valve seal I wouldn't even consider using rubber, technology has advanced far enough to offer much better performing sealing materials that can endure high friction rates and radical temperature changes,
like Teflon.

[Barnsnake]

Viton is not rubber. It is a very durable and chemical resistant seal material.

[lineslinger]

I should have said "rubber like" materials, because Barnsnake is right.
Viton is a synthetic based Fluoroelastomer developed by DuPont Dow Chemical co. I have used Viton based materials for other sealing/gaket applications and it is very cool stuff. There are 4 dedicated "types" of which certain compositions are not recommended for exposure to automotive or aviation fuels. Its ability to endure long term friction bearing exposure is what some builders question.
My builder has used both Viton and Teflon for valve seals. He has a bucket full of the Viton and other rubber type valve seals that he dumps off when they come in with cam kits etc. He swears by the longevity and durability of Teflon.

[sllib]

You guys need to check the dates on the posts you respond to. Jack21 passed away a few years ago.
Bill Stradtner

[trularin]

This is rich.

[dscott]

RIP Jack.....It's nice to know you can keep a post going after your gone! Jack did pass a few years ago.
Don