ACC has produced the best performing and most popular performance ignitions for over 20 years. The high energy spark of the CD design combined with multiple sparks resulted in a potent ignition. Not only did the multiple spark discharge (MSD) ignite the lean fuel mixture, it made overall improvements in the engine's starting, idle, emissions and power. MSD Ignition products are the finest ignition components you can install on your car whether it's a daily driver, dirt tracker, 4-wheel drive, a seven second Pro Stock car or Big Foot. MSD is your exclusive performance ignition company and we thank you for your interest and support.