Products and processes for analyzing octane content

A system for adjusting operation of a spark-ignition internal combustion engine having an electronic control unit (ECU) based on an octane measurement of fuel being delivered to the engine, the system comprising:

• an analyzer of octane ratings of the fuel in electronic communication with the ECU, the analyzer having a processor, a memory and a receptacle for sampling the fuel;
• the ECU is configured to periodically pump a sample of the fuel from a source to the receptacle;
• the analyzer is configured to:
• determine an octane rating of the sample by
• (1) forming a representation of a spectra of the sample, and
• (2) matching the spectra of the sample with a plurality of spectra having pre-assigned industry-accepted octane ratings, and
• (3) assigning to the sample a nearest recognized octane rating of the matching of the plurality of spectra;
• communicate to the ECU the octane rating assigned of the sample;
• and
• the ECU is configured to:
• adjust performance of the engine in accordance with the communicated octane rating, wherein the ECU (1) retards engine ignition timing when the communicated octane rating is lower than required for the engine, (2) advance engine ignition timing when the communicated octane rating is higher than required for the engine, and (3) do nothing when communicated octane rating are not determined.