MSD 8737 Three-Step Module Selector with Burnout, Launch, and Top-End Rev Limiters

The MSD 8737 Three-Step Module Selector gives drag racers and performance enthusiasts precise control over three independent RPM limits, each activated at a specific stage of the run. By plugging directly into the RPM module socket of a compatible MSD Soft Touch Rev Control or Timing Controller, this selector lets you dial in the exact RPM ceiling for your burnout, starting line launch, and top-end protection—all in one compact unit.

Each RPM limit is triggered by applying 12 volts to the corresponding activation wire. Connect one wire to your line-lock circuit to activate the burnout limiter, keeping tire temperatures consistent throughout the warm-up. When the line-lock is released, that limit shuts off automatically. At the starting line, the launch limiter is activated through a clutch or trans switch for a repeatable, consistent RPM that delivers firm holeshots on every pass. When no module is selected, the high-end rev limiter remains active by default, protecting the engine against over-rev in the event of driveline failure.

The 8737 can also be used with an MSD Timing Control in place of the RPM module socket. By inserting the selector into a retard module socket, racers can activate different ignition retard amounts at specific points during the run—an ideal setup for multi-stage nitrous systems. With the optional addition of an MSD RPM Activated Switch, the selector can also trigger a shift light at different RPM thresholds.

Key Features:

• Three selectable RPM limits: burnout rev limiter, launch/starting line rev limiter, and top-end/high-end rev limiter
• RPM modules are activated by applying 12 volts to the corresponding wire
• Default high-end module is active when no voltage is present on activation wires
• Compatible with MSD Soft Touch Rev Controls and any MSD Timing Control that uses plug-in modules
• Can be used as a multi-retard selector with MSD Timing Controls for nitrous or boost applications
• Black plastic housing with four included mounting screws
• Sold individually; RPM and retard modules are not included

The MSD 8737 is a must-have for serious drag racers looking to maximize consistency and protect their engine across every phase of a pass. Note: Must be used with an MSD Soft Touch Rev Control or a Timing Controller with a high-speed retard module. RPM modules are sold separately. Do not use solid core spark plug wires with any MSD component.