The more similar you can make the plate in thickness to the actual head, the more accurately it will simulate an actual head being torqued on the block. Also, you don't have to make the plate as wide as the real head, just only wide enough to reach to the pushrod area, beyond that has no affect on the cylinder walls, so that might make the initial cost a little cheaper(plus lighter). But im sure that having a 3/4" to 1" plate would be better than none at all, just add some spacers under the bolts to make up the difference.

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There's no such thing as too much cam....only not enough engine!

In a pinch I have used a block of iron and a head bolt on all 4 corners and just moved it down the head as I hone it.
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
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