These are the Off The Line Performance Street Series Ignition Coils. Once you start making more boost and more horsepower, you will have to upgrade your ignition system as a proper spark output is a key attribute when maintaining a smooth powerband throughout the RPM range while making big power numbers. The Off The Line Performance Ignition Coils have been tested on vehicles ranging from stock power levels to vehicles making over 1000 horsepower. These are direct replacements for your factory ignition coils for a plug-and-play installation.