Advance Lockout Kit GM HEI Distributor

The Advance Lockout Kit GM HEI Distributor from FAST Electronics is a precision ignition control component designed for GM High Energy Ignition systems undergoing performance modifications. Built for engine builders, hot rodders, and serious enthusiasts who demand reliable spark timing control during aggressive tuning, this lockout kit prevents unwanted advance curve variations that can cause detonation, timing scatter, or inconsistent ignition behavior under boost or high RPM conditions. If you're upgrading to a programmable ignition or running a carbureted big-block with custom timing requirements, this component is essential for maintaining stable, repeatable ignition events.

The Advance Lockout Kit works by mechanically locking out the centrifugal and vacuum advance mechanisms within the distributor, allowing you to control ignition timing exclusively through external tuning sources—whether that's a standalone ECU, carb tune, or dedicated ignition controller. This eliminates unwanted curve bleed-through that factory HEI distributors introduce, giving you precise, predictable timing control across the entire RPM band. The compact, lightweight design (0.05 lbs) integrates directly into the distributor housing without modification to your engine bay, and the precision-engineered lockout mechanism ensures zero mechanical drift or advance creep during sustained high-load operation.

Street cars, race engines, and performance street machines with GM HEI distributors benefit most from this upgrade, particularly those running forced induction, nitrous systems, or custom carb calibrations where timing accuracy directly impacts power output and engine safety. The kit is compatible with all GM HEI distributor configurations and installs in minutes without removing the distributor from the vehicle. Whether you're dialing in a freshly ported 454 or maximizing efficiency on a turbo LS swap, the Advance Lockout Kit gives you the ignition authority needed for repeatable, confident tuning.