273 commando Build

stroker402 said
here is a pic of a stock oem 273 commando 10:5 compression steele shim head gasket.... you can see the gasket is egg shaped toward the top near the valley ... could this be an issue with the way the chamber is shaped and the gasket I used. just say n . the composite gaskets I have been using are perfectly round.

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That is why you can't run a 3.625 bore gasket on a 273. You have to sandwich the gasket between 2 surfaces. Now put that gasket on to your head and see why you need that 3.95 dimension on a head gasket if your gasket fire ring is round.