Shell Ignition Model
 

I am using the Shell Ignition Model to simulate the ignition process in diesel engine. While I calibrated the model to such a point that the ignition timing is now correct, the peak pressure and peak heat release are both way too high. Anyone knows which parameter in the model could be adjusted to bring down both quantities?

Also, if the initial heat release is "missing", should adjusting the Shell Model helps at all?

Thanks.