Valve Seal ?

Has anyone used the white positive teflon valve guide seals? Thats what my motor guy used on my heads this time. Before I had the umbrella seals (viton) they worked fine.
[This message has been edited by HammerDown (edited February 27, 2002).]

I have heard that positive valve seals
are better than the umbrella type on
performance engines.

Actually, I believe if you look at some of Merc HP tech literature, you'll see that they recommend NO valve seal on the exhaust to (presumably) keep the valves a little cooler. Plus, unless you are luckier than me, if you're getting much horsepower out of a big block, you're going to be putting some oil through that motor anyway.
For what its worth, my 502 uses a quart every 4 to 10 hrs depending on how fast we have been going, or if we've just been cruising.
Maverick Originally posted by HammerDown:
Has anyone used the white positive teflon valve guide seals? Thats what my motor guy used on my heads this time. Before I had the umbrella seals (viton) they worked fine.
[This message has been edited by HammerDown (edited February 27, 2002).]

.
[This message has been edited by Racing Ray (edited March 12, 2002).]

Often positive seals are used just because of clearance problems with double springs its sometimes hard to get an umbrella seal to fit.With teflons you can machine the guide down for more clearance because they come in different sizes.Teflon is a little more heat resistant than viton.Either work very well.

I've always used the teflon, or PC seal, on the motors with no problem. As Racing Ray said a lot of guys don't run the seal on the exhaust, a lot of the Buick Stage 1 motors came from the factory like that if I recall correctly.
Craig

Thanks for all the reply's...feel some what better about them being on my stuff.
[This message has been edited by HammerDown (edited February 28, 2002).]