If your GM Coil has two connectors, usually one gray and one black, this is a direct replacement performance coil. This style coil was used on pretty much anything that came out of GM until 1996 (except DIS systems). MSD's Blaster GM Coil features a red housing that surrounds a set of Blaster 2 influenced windings for improved output. The Coil mounts in the same location as the stock coil and plugs right in. Note: If you plan to install an MSD Ignition with your Blaster GM Coil, use a PN 8876 Harness (see below) for a direct plug-in installation. BLASTER GM SPECIFICATIONS Primary Resistance: 0.45 ohms Secondary Resistance: 5.5K ohms Maximum Voltage: 48,000 volts Inductance: 7 mH Turns Ratio: 85:1 Peak Current: 220 mA Spark Duration: 250 Us Tested with an MSD 6AL at the plug gap. Application: Most GM vehicles with 2 plug coils up to 1996