Nothing beats bolt-on and direct connection components especially when they improve performance like this AeroflowPerformance GM 2 tower coils. Designed specifically for the GM/Holden engines used from the mid 1980's to late 1990's. The lower primary resistance produces a higher voltage output compared to the stock coil packs. This improved spark helps burn the fuel mixture more efficiently, resulting in smooth idle and heightened mid-range rpm power.