The Shorty configuration is ACCEL's patented race proven spark plugs. The overall length has been reduced from 3/16 in to 3/8 in (depending on the specific spark plug) to gain a critical air gap between the spark plug boot and the exhaust manifold or header tube. This helps eliminate burning the spark plug boot. Where there is not a lot of room to fit a socket or move a wrench around, shorter spark plug length also can make it easier to install and remove the spark plugs in certain applications. ACCEL Shorty Spark Plugs are made with a Copper core which is a better conductor than Platinum and Iridium. They deliver a stronger spark especially in high-performance applications where high combustion pressures are present. Copper is much better at dissipating heat than other materials which lessen the chance of a misfire. ACCEL Shorty Spark Plugs have custom gapping which allows you to open the gap exposing a larger flame kernel or close it if needed for high boost applications. All ACCEL Shorty Spark Plugs have machine-rolled threads allowing for a more precise thread engagement and torque retention.