Some Statistical, Technical, and Practical Issues in Virtual Engine Testing

API's Engine Oil Licensing and Certification System has implemented Provisional Licensing in response to a shortage of parts for the Sequence IIIE engine test. A Task Force delegated by the ASTM Sequence II/III Surveillance Panel was asked to develop a process, if appropriate, for the use of mathematical models as a substitute for the Sequence IIIE engine test. The Task Force tried to develop a fair and technically justifiable system for predicting engine oil performance based on models derived from existing engine test databases.

The situation appeared to some to be the ideal application for initiating and proving a virtual test approach. In the end, others said the situation was too time-constrained or limited in scope.

This paper describes some of the statistical, technical, and practical issues involved in specifying a process for virtual testing. Some perspectives on these issues as discussed in the Task Force effort are explored. The goal for the paper is to provide a record of work as a possible stepping stone for future efforts to establish virtual testing for demonstrating engine oil performance.