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Old 4th August 2021
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VE at cranking speed is 100 % ?

I would have to think carefully about that. Especially with very late closing intake cams.
To get 100% efficiency the valves would have to be fully closed at BDC.
At slower speeds some of the charge is going to be pushed back out of the combustion chamber.

The VE is going to change over engine RPMs as sometimes inertia of the incoming charge combines with a pressure wave happening at just the right time in the inlet tract to achieve effective VE higher than 100%.

At lower rpm's when the pressure waves are 180 degrees out it will work against you and reduce VE.

If you drop below the required VE the engine won't even start. You have to kick faster.

VE is only an approximated number. Static compression is an actual number but doesn't really tell you that much. And even with the best set up for checking cranking pressure it doesn't tell you the whole story as the pressure will rise in a running engine at high revs.

Of course, all of this is only my opinion and others may disagree.
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