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I can log the cam phasing pids just fine (I wish I could log ETC wtf?).
I'm just trying to figure out if 0 is max advance or not. I hit 24 degrees at WOT under boost on the intake cam, and 18 degrees on the exhaust. To me I would think the VVT being used as a EGR function would also pump my precious boost out the exhaust?
Jim
As I understand it, EGR works only during part throttle. It recirculates exhaust gas back in to the intake or in the case of VVT closes the exhaust valves earlier to prevent all of the exhaust gas from escaping, what is left in the engine is reintroduced during the next cycle.
So by looking at the exhaust cam map I would deduce that any numbers located in the area most expected to be used as EGR would be numbers that reflect the earliest exhaust cam closing time.
In my tables:
Attachment 2667
That would be the high values.
And for that fact alone making an assumption with the intake cam I would suspect that the opposite is true.
That's still doesn't tell us what 0 degrees is, but at least I'm beginning to feel confident on the direction they are going..
Anyone care to please provide any contradictory/complementary information to help this along a little?
As a continuation of this train of thought here are the cam profiles for the LE5 according to the ECOtec Cam sheet from GM.
LE5 Intake Cam - 12578511
Cam Peak Lift - 6.2551
Valve Peak lift - 10.542
Valve Timing - 135
Duration 1mm - 210.30
Valve area@1 - 1253.30
LE5 Exhaust cam - 12578512
Cam Peak Lift - 5.95143
Valve Peak lift - 10.0390
Valve Timing - -125
Duration 1mm - 195.40
Valve area@1 - 1092.70
From the delphi.com
(http://delphi.com/manufacturers/auto...alvetrain/vcp/)
Code:Control Valve Intake Exhaust Valve Overlap
Off Retard Advance Minimum
50% Intermediate: Flow is restricted to "hold" position.
100% Advance Retard Maximum
more on this later...