This MSD RPM Module Chip is a plug-in rev-limiter chip that sets a fixed 8,400 RPM ignition cutoff in compatible MSD ignition control boxes that accept interchangeable RPM modules, letting an engine builder or racer dial in a precise rev limit without reprogramming the box.
Specifications:
- Type: RPM Module Chip (plug-in rev limiter)
- RPM Setting: 8,400 RPM
- Packaging: Each
- Part Number: ASY11551
FAQ
What RPM does the MSD ASY11551 module set the ignition to cut out at?
It is a fixed 8,400 RPM module — the ignition box cuts spark once the engine reaches 8,400 RPM.
What does this module plug into?
It plugs into MSD ignition control boxes designed to accept interchangeable RPM module chips.
Can the RPM limit be changed later?
Not on this module — it is fixed at 8,400 RPM. Reaching a different rev limit requires swapping in a different MSD RPM module.

