Quote:
Originally Posted by Stan Weiss
Matt the reason I ask how you were calculating VE was your 150%.
The effective cylinder volume is the same as swept volume only calculated using the dynamic stroke or stated another way the cylinder volume @ intake valve close.
I use that term on the 2 stroke page because somewhere I found that is what they (2 strokers) use. On the CR page for 4 strokes I call it "Total Volume".
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I would not refer to this as being dynamic stroke. If you revolve the crank till the valve closes you then use this
static piston position to calculate cranking compression ratio and cranking
trapped volume. Dynamic stroke would be if at 6,000 rpms the crank flexes and the rods stretch to give an extra 0.50 piston stroke movement. Other two stroke tuners and a few in my circuit use the transfer port closing period to begin the dynamic stroke reference point as you suggest. Graham bell has suggested that this method got started this way because some of the cheaters have used this dynamic stroke to calculate dynamic displacement so as to justify a compensating increase in displacement that they then keep secret.
When I originally saw the trapped volume in your chart I thought this was taken dynamicly at maximum torque rpm so as to use the ram tuning and enertia to make this dynamic trapped volume bigger. I then thought we could plug in the dynamic compression ratio and volumetric efficiency but I hadn't realized that this number was in cc,s and that it was what I would call chamber volume. now that I know what you are trying to communicate my posts will also start to make a little more sense.
matt