Designed for 1974–1979 GM HEI distributors that are not computer controlled. This kit provides the parts needed to tailor ignition timing for improved performance.

• Fits GM HEI distributors (non-computer controlled, 1974–1979)
• Includes two weights and a center plate
• Three sets of color-coded springs for tuning advance rates
• Two pairs of nylon bushings
• Complete instructions included