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> Help me determine my compression ratio
Cevan
post Apr 14 2010, 11:45 AM
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So I've started my engine build and have the engine mocked up to measure the deck height. My preliminary measurements are around .030. I've got to do some juggling around of components to get them more equal to each other. Here's what I've got:

head volume: 58.2 CCs
bore: 96mm
stroke 71mm

Based on the cam I'm using here's what I get for different deck heights:

.040 static C/R 8.84:1 dynamic C/R 7.76:1
.050 8.63:1 7.57:1
.055 8.53:1 7.48:1
.060 8.43:1 7.4:1

The engine is going in a 914 (obviously) that will be used for spirited street driving. I have 93 octane gas available here. The car will be driven between sealevel and 1000'. I'm using webers with SSI H/Es and a Bursch muffler.
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Cevan
post Apr 15 2010, 08:52 AM
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So after refining and practicing my deck height measuring procedure, I get deck heights between .026 and .028. I think that's close enough.

If I use the .008 shim that comes in my gasket set, I'll have a C/R of 9:1. Will my final deck height of .034 be a problem? I'm using 2.0 heads that Len Hoffman minimally flycut.
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