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Discussion Starter · #1 ·
I'm finally getting my engine back together. I had the block deck surfaced, now I have .040 piston protrusion vs. std of .024-.028. If I go with the 1st oversize head gasket (.010 thicker than standard) it will put the effective piston protrusion at .030 and give slightly higher compression than standard. If I go with the 2nd OS (.020 thicker than std) it will put the effective piston protrusion at .020 and give slightly lower compression ratio than standard. I'm installing a new head so don't have to adjust for a shaved head. I'll be using an HY35 turbo which should build boost earlier than the stock one so I'm leaning towards using the 2nd OS but would like to hear the opinion of you guys who have built a lot of these engines.
 

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Usually guys go with lower compression in a Turbo Diesel during a rebuild if pistons are available. Lower compression = more room for boost/lower egt's.
 

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Discussion Starter · #4 ·
Great, thanks!
 
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