Inside the cap there are thick vanes to help agitate the air to prevent the chance of crossfire. Stainless terminals are used for resistance to corrosion caused by ozone in the cap. The rotor is also molded out of Rynite and features a brass/stainless steel rotor tip plus has a lock screw for secure mounting to the Mag's shaft.
MSD Pro-Mags are engineered for a wide variety of racing applications. Each Mag is supplied with a durable cap and rotor that has been tested for performance. When space permits, upgrading to a larger diameter magneto cap can further prevent chances of crossfire. Also, if you're using a timing control to retard the timing, a Cap-A-Dapt is highly recommended because the retard affects the rotor pha..
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