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patkeefe patkeefe is offline
one of the great unwashed
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Join Date: Apr 2004
Location: Ringwood, NJ
Posts: 2,850
Alan, I have had control pressure set from 2.8 bar to over 4 bar, and all points in between. If I raise it much past 4 bar I may as may as well not even have a WUR.

CIS typically leans out at higher RPM, so what I meant was I have the fuel to support boost at redline. The way I see it, it's easier to blow something up from detonation at 6500 RPM than it is at 3500 RPM. The mid range just has too much enrichment.

The simplified look at the fuel delivery is that the control pressure basically sets the pressure differential inside the fuel head, and the plunger off the air plate sets the volume to the injectors. More airflow past the plate, more fuel delivery (the slots get uncovered in the metering device). So, volume delivery to the injectors is somewhat independant of the WUR, but the pressure of the injector squirt is controlled by the WUR. I think the IA head gives more volume per unit pressure.

I may take the IA head apart to see how the thing was modified.

Patrick E. Keefe
78 SC
01 Boxster
Old 06-15-2008, 06:49 PM
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