J.C.-
As Paul said, you can't run them with o-rings. Sometimes you can mill the block carefully with the o-rings installed, and the ring will act like a filler, and then run the gasket on top. I have run gaskets of any type on the deck AFTER removing the rings, even with the grooves still in them, provided that the fire ring of the gasket surrounding the bore is closer to the bore than the groove. If the fire ring interferes with where the o-ring was, then you will have to fill it. The Cometics seal with raised embossments around the water holes and bore. If any of the embossments interefere with any holes, it will not seal. The standard type gaskets are more forgiving, so always check.
Bad69-
Cometic. You will not need to o-ring the block, run copper gaskets and receiver groove the head. The cometics work the best, and have no problem with them on crazier combinations that you will be running. They are a Multi Layered Steel (MLS) gasket, with the top and bottom coated. They do require a very smooth clean flat surface on both the heads and block to be optimum. And they do not go together with any silicone or copper spray. That actually hurts their ability to seal. Run them right out of the box, and they are reusable.
Joe Pontiac
Maximum Race Engines
www.maximumraceengines.com
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