>>compression of the existing engine is 110, 103, 108 and 105 psi
>>with the throttle open.
>But it's very good that the readings are so similiar.
Agreed
>A compression test is really ony good in a "relative" way. It will tell
>you if one or two cylinders may have a problem in relation to the other
>cylinders on the SAME engine.
Agreed
>Trying to relate your readings to another engine can be misleading since
>the cam profile, valve overlap, static compression can all be different.
Hummmm
I would be tempted to think that the dynamic compression, i.e. run with
all the plugs out, throttle open (I wedge the SU pistons open as well),
starter turning about 1,500 RPM, would be a excellent way to evaluate the
effective engine's compression (and octane required).
For instance, the static compression means little without a cam profile
and some means to calculate overlap's effect on the engine, BUT a
compression test would take this into account. Not quite the same as
a running engine, but certainly a much better approximation than any
other bench calculation.
Is this true? 170 psi the limit for street gas...?
Roger
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