LS2 Dynamic Airflow calculations

[flea]

Has anyone figured out the math behind the dynamic airflow prediction coefficients for the LS2s (E40)?

e.g. dynamic airflow gain for current MAP component, etc.

Are the values additive or used to come up with the values for the corrected airmass (or the corrected airmass values added to the other gain numbers)?

I've created a PID that calculates GMVE and I'm trying to determine the influence of the dynamic airflow calculations on GMVE.

Any info on how/when the VE correction factor comes into play would be helpful as well.

I'll post the PID (and histo) for GMVE if anyone is interested.

[redhardsupra]

cylairmass=GMVE*MAP/TEMP
totalairflow=cylairmass*rpm*cyl/120

[flea]

RHS,

I should have taken a little more time to explain. What I'm referring to are the following (among others).

Thanks

[flea]

I'm not seeing my attachments ........

[5_Liter_Eater]

I see them in both posts.

I disabled dyn airflow a few months back. Running MAF only. No issues to date and it's soothing not having to worry about my VE values.

[flea]

Bill,

What rpm settings (enable/disable) have you experimented with? Right now if I go much below 2800/2700 I begin to lose AFR consistency.

[5_Liter_Eater]

I have the disable set at 600 and re-enable at 500. May as well have set them at 1 and 0. I have what I would consider a "big" cam and I don't have any problems with MAF only.

[rob82]

In the GENIII the VE table was still referenced even when using the MAF as the source of it airmass calculations. Think it was to help in large transient situations. Maybe the dynmaic airlfow corection is a similar table?

Have seen other systems use similar correction values to drive the 02 sensors into oscillation. Maybe some could explain fully as I havn't had time to investigate.

[flea]

In the GENIII the VE table was still referenced even when using the MAF as the source of it airmass calculations. Think it was to help in large transient situations. Maybe the dynmaic airlfow corection is a similar table?

Have seen other systems use similar correction values to drive the 02 sensors into oscillation. Maybe some could explain fully as I havn't had time to investigate.

Based on my experience the VE table is still being referenced to some (minor?) extent with the E40 LS2s with dyn airflow supposedly disabled.

If anyone has different info feel free to share

[Blades]

cylairmass=GMVE*MAP/TEMP
totalairflow=cylairmass*rpm*cyl/120

What is the 120 constant?

[redhardsupra]

120=2*60 2 because you get one injection/ignition per two revolutions, and 60 to convert from revs per minute to revs per second