Hey all, i know these are fairly old ecms/motors and this section of the forum rarely gets visited, but i believe ive came up with a way to scan/log your cam angle on the 4200 vortec.
It gets annoying having to go back to the VCM and find what your angle is at a given point, and theres no "cam angle/desired cam angle" PID's in the scanner. I cant say FOR SURE this is correct, but so far it lines up with what my programmed cam tables are supposed to be.
These trucks don't have an EGR, but what they do have is VVT capabilities; I see in the scanner there is "EGR Pintle Position" [2810] and "EGR Desired Pintle Position" [2812]. So i logged those two in my Channels section and noticed they closely follow one another and seem to closely match my cam tables at given rpms. Like for example around 5800, I'm commanding 24 degrees of cam retard, and i noticed the EGR position was 95% or so. (the total travel of the cam is 25 degrees from 0). It seems to move up and down with knock retard as it should as well.


So in user maths, i created two maths.
Cam Angle - "([2810.156] / 100) * (25 - 0) + 0" (1 Decimal Place)
Desired Cam Angle - "([2812.156] / 100) * (25 - 0) + 0" (1 Decimal place)

The breakdown of this is as follows: (percentage / 100) * (range_max - range_min) + range_min = Angle

Using these maths, then outputting them into your chart vs time or wherever, you can now get a get idea of what your cam is doing, and what its being commanded to do.
Hope this helps future 4200 tuners