Why is the program predicting more performance than Im seeing on the dyno (or at the track)?
Simulation programs are predicting how things should work with all systems working properly, carbs metering properly, ignition systems firing perfectly every time, combustion chambers burning efficiently every firing, etc. They can predict a mis-match of parts, but can not predict a improper operation or failure of some component. Therefore, programs are usually predicting “best case” performance.