Review on ACDelco 17 Professional RAPIDFIRE Spark: Ultimate Performance for Optimal Ignition by Mark Deuschle

I used it to set up my messenger and it helped a lot. The inline 6 idled rough and consumed 1-2 mpg less than usual. After replacement, the engine began to run more smoothly. While this is an oversize, you should make sure it is the correct spacing for your car and double check all as the incorrectly sized spacing can be accidentally framed. They last longer than copper cores. , and for a daily driver this is ideal because you don't have to change it every 20-30k, now every 50-100k depending on how and where you drive.