Billet Chrysler Small Block Distributor Chrysler Small Block La 273/318/340/360 Must Be Used With 6, 7, Or 8 Series MSD IgnitionSupporting the advance assembly is a hardened, polished steel shaft. Two ball pickup creating a trigger signal that tells the MSD to fire. bearing guides are used to support the shaft producing incredible stability. Precision paddles of a zinc plated reluctor pass a maintenance free magnetic Get your Mopar fired up with billet accuracy and performance. Remove the MSD cap and Race Rotor and you'll find easy access to the adjustable mechanical advance