Modular Spark plug list! - Credit to Juiced46 (Dave) MOTORCRAFT PART# / HEAT RANGE AWSF-32C / stock heat range - copper plug AWSF-22C / 1 Heat range colder - copper plug AWSFA-12C / 2 Hea range cooler - copper plug AGSF-32C/ Recommended for FRPP heads(not sure on heat range) NGK PART# / HEAT RANGE TR-55/ 3951/ Stock Heat Range TR-6/ 4177/ 1 Step Colder BP7EFS (PN - 3526) BR7EF (PN - 3346) two steps R5724-8 (PN - 7317) two and a half steps R5724-9 (PN - 7891) three steps R5724-10 (PN - 7993) four steps AUTOLITE PART# / HEAT RANGE 764s / Stock 103s / 1 heat range cooler AR94 / 2 heat range cooler AR93 / 3 heat range cooler AR92 / 4 heat range cooler CHAMPION PART# / HEAT RANGE YS-59C / -3 or -4 below stock heat range DENSO PART# / HEAT RANGE IT16 / stock heat IT20 / -1 heat range IT22 / -2 heat range IT24 / -3 heat range

wow this is an awesome find, thanks helped me figure out the proper plug much easier then lookin all over the comp

There is another autolite avalible. AR103's same heat range as the regular 103's, but with the AR slant cut electrode for more performance.