Spark Advance Lockout - Mechanical / Vacuum - Aluminum - GM HEI Distributors - Each

Vacuum Advance Lock Out - Plastic - GM HEI Distributors - Each

Distributor Lock Out - Mechanical Advance Lock Out - GM HEI - Each

Distributor Lock Out - Vacuum Advance Lock Out - GM HEI - Each

Spark Advance Lockout - Aluminum - Natural - Pertronix Flamethrower Distributors - Each

Upgrade your engine's performance with the HEI Vacuum Advance Stop Plate by MSD IGNITION. This innovative kit limits vacuum advance, ensuring precise timing for optimal power output. Say goodbye to inconsistent spark advance and hello to smoother...