View Single Post
Old 02-01-2019, 12:14 PM   #89
Ski in NC
Technical Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 6,194
Seems like a circular discussion. Torque is not measured. Fuel flow is not measured.

ECU has rpm measurement, crank position sensing, charge air measurement, along with various temps and pressures. Input rpm request from helm. Output from fuel map is injector open times, timing, rail pressure, etc.

But in the above algorithm, the data points can be compared to data taken when the (or same model) engine was on the factory dyno. On the dyno they DO measure torque and fuel burn with lab quality equipment. Those dyno data are stored in the ECU.

So where ever you are operating the engine, ECU can look up in its tables and see what the torque and fuel burn should be based on the dyno data and current operating parameters. That is what is displayed. No need to actually measure. Measuring torque and burn directly requires expensive and sensitive equipment.
Ski in NC is offline   Reply With Quote