When I dyno an engine using an Inertia Dyno and your DataMite, the HP seems to peak too early, say 9,500 RPM, when I actually rev the engine to 10,500 RPM on the track. Why?
There are several reasons: For best performance you do want to rev the engine past the HP peak. For best performance, you want to keep the engine in the highest HP range available. This usually means revving past the peak, so the lowest RPM on the track is still near the HP peak. The dyno can only show performance for the RPM range you have tested. In simplest terms, it can’t show you torque and HP at 10,000 RPM if you don’t rev it to at least 10,000 RPM. Most all dyno data looses accuracy near the point where you open or close the throttle. This is usually the start and the end of the run. One reason can be due to not knowing exactly where the throttle closes. Another is that in the process of filtering (smoothing) data, the data happening a small time before and after some event gets averaged in with the event. This means that data at 9800 and 10,200 RPM gets averaged in with data at 10,000 RPM. Since 10,200 RPM may be very low power (closed throttle), it will bring down the average
Related Questions
- When I dyno an engine using an Inertia Dyno and your DataMite, the HP seems to peak too early, say 9,500 RPM, when I actually rev the engine to 10,500 RPM on the track. Why?
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