Setting MAF and RPM on dyno

Hello,

After watching this video (correcting yout AFR in the EFI course), I have a technical newbie question.

When tuning one cell in the VE table, you need to put the engine in the right "state" meaning it needs to run at the MAF of this cell (40, 50, 60) and also run at the right RPM (2000).

The way I understand it, is that you open the throttle to achieve the right MAF, but what about the RPM? Do you set the required RPM on the dyno and it will increase/decrease the load on the tires to fit this RPM?

Thank you!

Best regards,

Tomy

Hey Tomy

With a loaded dyno, like a eddy current one, the dyno software will need to have a RPM signal, or interpolate the engine RPM from the roll speed. You can then set the dyno to hold the RPM and it will adjust the load to keep the RPM constant. This is called steady state tuning, the RPM stays the same and you adjust your VE table load cells for this particular RPM.

If you do not have a loaded dyno, you can't do steady state tuning, when you open the throttle the RPM will increase.

Frank described VE table tuning.

Since you also mentioned MAF, that is more often done with sweeps since it is not RPM based and this speeds the process.

If your ECU has both MAF and VE based tuning, it's often more simple to tune one system at a time, then verify operation with both active after.

Excellent, Thank you both for your answers!