Influence of Carbureter Setting and Spark Timing on Knock Ratings - Annual Meeting Paper

THAT the antiknock quality of a motor fuel is best determined by comparison with a standard or reference fuel is generally agreed. The results of the investigation described in this paper show how this comparison may be affected either by the carbureter adjustment or by the spark timing or by both. Therefore, in establishing a standard method of comparing one fuel with another, some definite specification covering each of these two engine-variables must be drawn up. This specification should correspond reasonably well with conventional conditions of engine operation and at the same time with convenient laboratory technique. From the results of this study these conditions would appear to be fulfilled best by using the carbureter setting for maximum knock and the spark timing for maximum power.