1997-2004 GM Cars w/VIN G/S - 1998-2006 GM Trucks w/VIN E/D (8th Digit) - Additional 2-Pin Connector. MSD's engineering team has been working diligently the past year to improve our Multiple Spark Coils for the GM LS-engine platform. The coils fit in place of the OEM coils yet are capable of delivering higher spark energy to the plugs, topped with multiple sparks at idle rpm. Increased spark energy and voltage, along with multiple spark capabilities, help improve the combustion process of the fuel mixture to create an efficient burn. This results in improved throttle response, smooth idle and quick starts, plus increased high rpm performance! Connector and Plug Wire on the same side. The 2-pin connector must be plugged into the coil. If not, the coil will not operate. This additional connector is for optional ignition/timing control.. Cadillac CTS (05-04) Chevrolet Avalanche 2500 (02) Chevrolet C3500 (03-01) Chevrolet C3500HD (02-01) Chevrolet C6500 Kodiak (00-99) Chevrolet C7500 Kodiak (00-99) Chevrolet Camaro (02-98) Chevrolet Corvette (04-97) Chevrolet Express 3500 (02-01) Chevrolet P30 (99-98) Chevrolet Silverado 2500 HD (02-01) Chevrolet Silverado 3500 (02-01) Chevrolet Suburban 2500 (02-01) GMC B7 (02-99) GMC C3500 (02-01) GMC C3500HD (02-01) GMC C6500 Topkick (02-99) GMC C7500 Topkick (02-99) GMC P3500 (98) GMC Savana 3500 (02-01) GMC Sierra 2500 HD (02-01) GMC Sierra 3500 (02-01) GMC Yukon XL 2500 (02-01) Pontiac Firebird (02-98) Pontiac GTO (04) Workhorse Custom Chassis P32 (03-01) Workhorse Custom Chassis W22 (03-01)