Yes originally just the O ring. I used both O ring and umbrella seal on my 327

 

Thanks for the reply, I'm gonna use both as well. Seems like the right way to go.

 

Do the umbrella seals you have fit over the valve guide boss ?

 

Yes they slide over the valve guide boss. They aren't tight on the boss just tight on the valve stem. I would imagine they were designed to ride up and down on the valve guide boss. Does that make sense?
Thanks,
Chris

 

That does make sense but usually on those older heads the guide bosses are too big for those seals to fit over them. I wonder if somebody has machined yours down in the past ? Doesnt matter as long as they work

 

The umbrella seal from what I have used. Stays locked on the head. Stock heads need machined for them

 

Interesting, from what I can see these umbrella seals Fel-pro SS 10058 have no way to lock onto the head. The heads have not been machined in anyway. I think the locking type is a newer and better seal but I don't plan on having the heads machined.

 

If they are leaking oil u may want check the guides. The o ring seals work well, if it burns oil, it should be just for a second on start up,

 

Picture of Fel Pro SS10058 seals. https://www.summitracing.com/parts/fel-ss10058

 

No Smoke at start up. The heads are GM part number 3890462. I'll take a picture of the fit when I get back from the Camaro Nationals this weekend. Thanks to everyone who replied.

 

I have used the umbrella seals on several engines and they fit over all of my valve guides.