Standard Preignition Rating of Spark Plugs 1999-11-15 HISTORICAL J549_199911 This SAE Recommended Practice describes the equipment and procedures used in obtaining preignition ratings of spark plugs.
Standard Preignition Rating of Spark Plugs 2013-03-11 HISTORICAL J549_201303 This SAE Recommended Practice describes the equipment and procedures used in obtaining preignition ratings of spark plugs.