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Discussion Starter #1
Anybody know the distance from the bottom of the head at the spark plug hole to the top of the piston at TDC for regular pistons and for Motronic pistons on a 2L engine?

Thanks
 

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For stock pistons it is about 0.5". It is a bit more with Motronics and a bit less with 10.4 Borgo's. I used to have the exact numbers but I cannot find them.
 

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Discussion Starter #3
I thought Motronics were a tad taller than stock. I thought they were later pistons that gave a little more compression.
 

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The ones that I measured were lower.
There were certainly different Motronic pistons but I thought that the only difference was in piston ring sizes.
 

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Richard Jemison
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That distance is irrelevant. If you are using larger valves and (or) high lift cams you don`t use extended sparkplugs, unless they are carefully indexed.
 

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I thought that request was to determine which pistons are in an engine without pulling the head. Maybe I made the wrong assumption.
 
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