When you add an aftermarket ignition box to a car that still runs a GM HEI distributor, the factory HEI module becomes redundant and the box needs a clean trigger signal from the magnetic pickup instead. This cable makes that connection, wiring the ignition or timing accessory straight to the pickup inside the distributor so the HEI module is bypassed.

MSD 8861 Module Bypass Cable Features:

• Connects a 6 or 7 Series ignition or timing accessory to the magnetic trigger inside a GM HEI distributor.
• Bypasses the factory HEI ignition module.
• Also adapts to the harness on 6M-2, 6-Offroad and 8 Series ignition controls.
• Terminated connectors on both ends, no splicing required.