having read the technical information on the Topbuzz website, i'm not convinced that a head that has a core plug makes it a KS Head.
My engine came out of an '88 Astra GTE 16V; one of the first red-top valver engine's.
Mine does have a core plug on the side of it but also has a cast camshaft cap date of '87 (located below oil filler cap), so i can't see how it can be a KS Head.
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