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Head Gasket Bore / Thickness

Don Dada

By Don Dada,
in Engines & Forced Induction

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Don Dada Mentor

Don Dada

Posted
Posted

Ok guys need some input here.

I'm in the process of ordering parts for a rebuild and so far i've sourced CP 20thou 8.5:1 pistons and an ACL main/rod bearing kit.

The problem is with the head gasket--- I'm only getting 87mm cometic gasket. Will this work with the 86.5mm bore?

An should i wait till the machinist deck/shave the block and the head then determine what thickness hg to use?

I want to maintain a CR of 9:1 or for the least 8.8:1

I guess decking/shaving and using a thinner HG would be the only way to bring compression back up since i cant seem to find 9:1 oversized CP pistons.

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https://www.sau.com.au/forums/topic/240776-head-gasket-bore-thickness/
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Kranker Collaborator

Kranker

Posted
Posted

yep, pretty sure .5mm over is the way to go for a head gasket

but im no engine builder, im sure someone with more experience will correct me if im wrong

CC ur head, then work out the CR with a 1mm gasket, then a 1.1mm so on and so forth, then you can work out which gasket you want to use, and/or how much the head needs to be shaved

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