In a message dated 27/04/2004 5:25:35 PM Pacific Standard Time,
owner-mgs-digest@autox.team.net writes:
Regarding compression ratio, you have to measure the volume of the swept
cylinder and the combustion chamber when the engine is apart. I also have
the slighlty dished h/c pistons which have a dish volume of about 6.5- 7
cc., and if you are bored over .060 your cylinder volume is 1868cc /4 =
467cc, but unless your head is removed you will not be able to measure your
combustion chamber.
As a matter of fact, you can do a better job figuring out actual compression
ratio by measuring with the head on. Tilt the engine stand so the plug hole
is uppermost and with the piston at TDC run light oil inot the hole until it
reaches the lower plug thread. Use that as your total combustion volume and
the calculated swept volume to calculate compression ratio.
Of course you need to have both valves closed when you do this....;-)
Bill
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