The digital Octane Analyzer option integrates with the XCP panel for a semi-automated fuel rating process that significantly reduces operator involvement and provides more consistent rating results. Using a bracketing procedure, the Octane Analyzer automatically sequences though the fuel sample and two primaries to determine octane numbers per ASTM methods. This process allows rapid selection and measurement of the fuel/air ratio for maximum knock value and reduces the time required to complete octane number determinations. The Octane Analyzer can run fuel samples in a bracketing mode in approximately 20 minutes for a full octane number determination.