The 1st Generation Sierra propelled GMC into the 21st century as its best-selling vehicle. With optional LS power, the Sierra can be just as capable at the track as it is the worksite. Whether you're building an all-around street machine, off-roader, or track weapon, Holley has the parts you need to make your dream a reality.

Creates a considerably hotter spark that lets the flame expand more rapidly in the combustion chamber and a more complete and efficient burn of the air/fuel mixture