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12:1 or 12.5:1 cr pistons for ea81?

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A friend of mine from Alaska told me that he heard of a company making high compression pistons for ea81 . Anyone heard of that? Also does anyone know what the cr would be on an ea81 with .040" head shave and ea71 pistons?

A friend of mine from Alaska told me that he heard of a company making high compression pistons for ea81 . Anyone heard of that? Also does anyone know what the cr would be on an ea81 with .040" head shave and ea71 pistons?

 

At .040" you would be looking at a custom intake as well. The waterports on the intake will not match up corrctly to the head. Not sure of the compression. I know there is an equation for it but can't remember it.

With that high a compresison ratio (12-12.5:1), you will have to use racing/aviation fuel or LPG.

11.5:1 would be manageable on the street, with a recurved disty. you would have to have your cam reground too, just so you could start it.

shaving the heads 40thou is good for about half a point.

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