|Knock sensor vehicle test program /
Landman, Larry C.
|Environmental Protection Agency, Ann Arbor, MI. Control Technology Assessment and Characterization Branch.
| Environmental Protection Agency, Emission Control Technology Division, Control Technology Assessment and Characterization Branch,
Exhaust emissions ;
Fuel consumption ;
Ignition systems ;
Octane number ;
Performance evaluation ;
General Motors vehicles ;
|NVFEL Library/Ann Arbor, MI
|Some EPA libraries have a fiche copy filed under the call number shown.
|51 pages : illustrations ; 28 cm
This test program was designed to explore the impact of an ignition system with spark knock sensoring and spark retard on regulated emissions, fuel economy, and power as a function of the research octane number (RON) of the test fuel. Currently, General Motors (GM) incorporates a spark knock sensor in a feedback ignition system on their turbocharged vehicles. This type of spark timing system is well suited to turbocharged engines because of their wide range of spark timing requirements. GM and others are also currently producing naturally aspirated engines equipped with knock sensors. The feedback aspect of this type of ignition system would allow the vehicle to automatically compensate the timing for the octane of the fuel being consumed. This technology could improve fuel economy of vehicles in service. It is conceivable that some vehicles incorporating a knock sensor timing system could have lower exhaust emissions and higher fuel economy using EPA standard test fuel (Indolene HO III) compared to operating with lower octane commercial unleaded gasolines. The knock sensor can be integrated into a spark timing system in a variety of fashions. This design variability precludes any generalized conclusions about the effects of varying the fuel octane rating.
Includes bibliographical references. "October, 1981."