In its original design, the Model A Ford did not feature a mechanism for automatic spark ignition timing (advance and retard). The driver manually controlled timing from the steering column (similar to that of the Model T). For optimum fuel burn energy, spark timing should be advanced between 10 to 12 degrees per thousand engine RPM. For the 2800 RPM A engine, this should be 28 to 33 degrees. This Nu-Rex mechanical advance system has been designed to provide 30 degrees of range and is designed for use on all Model A and B engines. The external appearance remains unchanged. Its simple installation requires absolutely no modifications to the distributor, engine, or timing procedures. The kit consists of three pieces:
• Centrifugal advance mechanism
• Replacement shaft to couple it to the unmodified distributor
• Replacement spring to hold the oil gear shaft in place.
Unskilled Model A drivers can now enjoy optimum performance at all speeds. This is a genuine Nu-Rex part.