MSD 8677 Adjustable Low RPM Module 1000-3000 RPM Two-Step Launch Control

The MSD 8677 Adjustable Low RPM Module gives racers and performance enthusiasts precise, on-the-fly control over their launch RPM set point without swapping fixed modules. By turning a simple potentiometer with a small flathead screwdriver, the user can dial in any RPM limit between 1,000 and 3,000 RPM — with each full turn of the adjustment screw equating to approximately 100 RPM of change.

Key Features:

• Fully adjustable range: 1,000–3,000 RPM — no fixed chips to swap
• Simple adjustment: Turn the side-mounted potentiometer with a small flathead screwdriver
• ~100 RPM per turn for fine, repeatable tuning
• Red plastic housing for easy identification
• Compatible with MSD Two-Step Module Selectors, Soft Touch Rev Controls, RPM-Activated Switches, and Shift Lights
• Plugs directly into the RPM module receptacle — no wiring required
• Legal for sale and use on emissions-controlled vehicles, non-emissions-controlled vehicles, and racing applications
• Sold individually

The MSD 8677 is especially well-suited for vehicles with automatic transmissions running MSD's Two-Step Module Selector, where a consistent, tunable launch RPM below 3,000 is critical for optimal 60-foot times. The module ships from the factory with the adjusting screw turned all the way in, corresponding to the highest RPM setting in the range. Note: this module is not compatible with the MSD Engine Governor (MSD 8725).