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Old 02-16-2012, 04:28 PM   #15
iminhell
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The first section in blue is what compression should hit by 'shaving the head', that is having a machine shop remove material from mating surface of the head to block.

The Red is the same thing but using the standard zetec head gasket.

SVT Head Raise Compression:

shaving the head (in cm),

standard SVT head gasket (.041" or 1.0414mm),


0.0254 --- 47.536040727 --- 10.507816645
0.0508 --- 46.101493218 --- 10.834790050
0.0762 --- 44.666945709 --- 11.182765960
0.1016 --- 43.232398200 --- 11.553835105
0.1270 --- 41.797850691 --- 11.950375240





with just using the .027" (standard Zetec) head gasket

0.06858 --- 47.017581344 --- 10.62368556


with Zetec head gasket (.027" or 0.6858mm)


0.0254 --- 45.583033835 --- 10.958024466
0.0508 --- 44.148486326 --- 11.314091186
0.0762 --- 42.713938817 --- 11.694074905
0.1016 --- 41.279391308 --- 12.100469124
0.1270 --- 39.844843799 --- 12.536126444






So, by just using the standard zetec head gasket your compression is raised to 10.6:1.

If you want to go 11.5-12:1 you'll have to shave the head (or buy high compression pistons and connecting rods).
So you'll have to shave from 0.0800-0.1270cm (or 0.0315-0.0500in).
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