MSD Atomic LS
For a company made famous by its little red ignition boxes, MSD has made a habit out of revolutionizing the muscle car market with its outside-the-box thinking. First came the 6LS ignition system, which allowed hot rodders to replace the hassle-ridden factory EFI systems found on LS-series small-blocks with carburetors. Building upon that groundwork, MSD has taken the next rational step by creating an easy-to-use stand-alone EFI system that eliminates the need to spend hours hacking into and tuning a factory computer. MSD's latest weapon is called Atomic LS EFI, and while the approach is slightly different than the 6LS, the simplicity and performance benefits are the same. The Atomic LS system essentially intercepts the factory EFI-related sensors, reroutes them to a stand-alone ECU, then uses MSD's proprietary self-learning software to tune the motor to perfection.

It works like this: Let's say you just unpacked a brand-new LS crate motor, or pulled a used stocker out of a donor car. In the past, retaining the factory EFI system required sifting through wiring diagrams to figure out which 20 percent of the stock wiring harness to keep, and which 80 percent to throw away. Likewise, tuning the stock computer involved shelling out hundreds of dollars on tuning software, renting dyno time, and possibly even hiring a professional tuner. Thanks to MSD's Atomic LS, all that's changed.

The system is so easy to install that the only components included in the entire kit are the ECU, fuel rails, a power module, a wiring harness, an oxygen sensor, and a handheld controller. The Atomic LS fuel rails bolt in place of the stock units and plug right into the factory fuel injectors. By integrating the ECU into the fuel rails, MSD has substantially cut down on the wiring. All the pertinent stock GM sensors and electronic gizmos—such as the throttle position sensor, injectors, coil packs, and manifold pressure sensor—plug right into connectors protruding from the fuel rails. As such, the main wiring harness is nothing more than a means to hook the EFI system up to a 12V power source.

As an industry stalwart in cutting-edge ignition control technology, MSD packed the Atomic LS's Power Module full of trick features. In addition to allowing spark advance control through the handheld controller, the Power Module offers nitrous timing retard and two-step launch rpm control. Furthermore, two different high-pressure fuel system options are available as well.

The goal with the Atomic LS system was to make EFI simple and clean up the engine compartment by reducing the amount of wiring." —MSD's Todd Ryden

By The Numbers
What's included: ECU, fuel rails, power module, wiring harness, oxygen sensor, handheld controller, EFI software
Max power: 1,000 hp
Injector size: N/A
Base kit PN: 2950 (LS2/LS3), 2960 (LS7)
Optional items: LS1/LS6 injector adapters (PN 2955), throttle body (PN 2940), high-pressure fuel system (PN 2920 and 2921)
Dealer network: yes, visit website for details
Street price: $2,495