Valve stem seals, Teflon or Viton ?

CobraV8 · #1 (**permalink**) 01-03-2011, 10:12 AM

Viton is said to increase oil consumption, Teflon causes the valves to run dry and increases guide wear...you find a lot of opinions on the internet, so what works better from your actual experience?

Simon

carmine · #2 (**permalink**) 01-03-2011, 10:57 AM

Viton worked for me.

blykins · #3 (**permalink**) 01-03-2011, 11:41 AM

I use Viton seals on everything I do...

And you're absolutely right, you'll find lots of opinions on the internet, even from guys who have never done it before. Best to ask the guys who do head work or build engines for a living...

FWB · #4 (**permalink**) 01-03-2011, 12:33 PM

i have the viton in my engine......can't really say if i notice oil consumption or not...
if i had to buy seals again, i would buy the viton....

bobcowan · #5 (**permalink**) 01-03-2011, 02:17 PM

I use Dart heads, and Dart seals. AFAIK, the seals are rubber. I replace them every 2 years or so, but they seem to be fine.

On mild street engines, I use the stock replacement rubber umbrella seals. They last easily 100K miles, and they're cheap. Not as good a seal as the other type, but doesn't seem to matter much in that application.

CobraV8 · #6 (**permalink**) 01-04-2011, 01:22 PM

I had some bad luck with the stock seals, as far as I know these are viton.

That's what the valves looked like:

Less than 5000miles on the heads, no measureable wear of the guides.

I need seals with a smaller outer diameter for my new springs anyway, so I ordered a set of these teflon seals: http://www.summitracing.com/parts/HRS-93315/

They really seem to seal "air tight" when installed. When moving the valve up and down you can feel they put a lot more friction on the valve stem than the softer Viton seals.

They also seem to have a nicer fit on the valve guides.

Is there anyone who had good results with the teflon seals? Or should I just get a set of viton seals with a smaller outer diameter...

blykins · #7 (**permalink**) 01-04-2011, 01:25 PM

Which Viton seals were you looking at?

I use the ones from US Seal....I think Comp Cams sells them under their own name.

CobraV8 · #8 (**permalink**) 01-04-2011, 01:35 PM

I guess these are the ones you're talking about? http://www.summitracing.com/parts/CCA-529-16/

I'm gonna have a look at them...

Thanks,

Simon

blykins · #9 (**permalink**) 01-04-2011, 02:40 PM

I don't like the ones that Edelbrock provide because of the metal lock ring around them.

The ones from US Seal are the ones that I use....they fit very well around the valve stem and the little spring around the top keeps them tight. Instead of a little rock ring around them to keep them under tension, the whole seal is encapsulated in a hard container.