Autotune ™ Feature.
The Autotune ™ feature is
available for the SMC and SM2 model ECU's.
An Autronic exhaust gas analyzer or any other analyzer that provides a 0 to 1 volt corrected output, is connected to the ECU O2 I/P, this is used as the actual air fuel ratio input. As the engine is run through its various RPM and Load points the software will adjust the volumetric efficiency numbers in the main fuel table to achieve the target air fuel ratio.
At no time do you need to touch the keyboard on the Laptop.
After the tuning is complete the analyzer and 02 sensor is longer need. At any time after tuning is finished the values in the target closed loop table can be changed, and the engine will automatically run the new air fuel ratio, providing you do not make a change to the volumetric efficiency of the engine, e.g. fit a different camshaft, modify cylinder head etc...
If the engine is modified so the volumetric efficiency changes, then the analyzer and Autotune ™ software will be required again to re-tune the engine.
The Autotune ™ software is much faster then a good operator. It is not possible to manually tune as quick as the Autotune ™. A typical engine will take less than 20 minutes to fully map on an engine dyno.
The accuracy of the Autotune ™ can be setup in the software from 0.5% to 5.0% accuracy. The default value is 2% accuracy, this is generally a lot more accuracy then most tuners manual tune engines.
This software uses a complex combination of math, including statistics, trigonometry and fuzzy logic to intelligently adjust the fuel delivery tables. Initial tuning is rapid usually occurring within 1 second. High precision can be achieved by allowing the Autotune ™ to operate for an extended time at each engine operating point. The operator has control over the balance between tuning speed and accuracy. Accuracy is ultimately limited by the accuracy of the attached Air/Fuel ratio measurement equipment.
The program provides visual indication of the tune status. Automatic and manual storage of tune status allows the user to monitor the tuning progress even if undertaken in several sessions. Tuning usually proceeds 2 to 5 times faster than possible by manual means. Fuel savings of as much at 90% have been reported. The considerable savings in engine life are obvious.
This program also has elaborate diagnostics facilities and allows simultaneous operation of the ECU internal data logger and external P.C data logging.
Versions are now available that have live
engine operating data graphs while tuning, and a live 3D graphical
presentation of the tuning process.
Copyright © 2002 Ray Hall Turbos. Autronic