High Compression Heads and Bore Size
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JBog
Topic author - Posts: 287
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High Compression Heads and Bore Size
Can you use a high compression head if your bore size and pistons are not stock? For example, my pistons are .030, would a Z head have issues?
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Kerry
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Re: High Compression Heads and Bore Size
No issues with bore size, just piston height needs to be checked.
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Allan
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Re: High Compression Heads and Bore Size
There are inconsistencies with some Z heads. They need to be carefully matched to the cylinder block. Oversize pistons are not the worry. You just might have to do a little re-shaping of the combustion chamber at the interface with the gasket.
The Prus heads are a better choice in my opinion.
Allan from down under.
The Prus heads are a better choice in my opinion.
Allan from down under.
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Tim D
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Re: High Compression Heads and Bore Size
I have been running a Z head for 20 years and my block is bored .080" over. with alum pistons. No problems.
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Tmooreheadf
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Re: High Compression Heads and Bore Size
The last Z head I used required some relief grinding on the interior edged on all 4 chambers to prevent piston interference on a .030 oversized bore. I tried a Prus head on another engine bored .030 over with no modification needed. Prus advertises .080 with no interference and that seems to be correct.
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JBog
Topic author - Posts: 287
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Re: High Compression Heads and Bore Size
Thanks, guys!