The Model T Ford Ignition System Spark Timing（福特T型汽车点火系统引发时机）.pdf

The Model T Ford Ignition System Spark Timing By Ron Patterson Steve Coniff With the possible exception of the planetary transmis- Before we discuss the details of spark timing, lets sion, no part of the Model T Ford’s original design is more review the unique features of the various components of the commonly misunderstood than the magneto ignition original Model T ignition system. system. The purpose of this article is to simply explain how Figure 1 is an original Ford timer case and roller. This the Model T Ford ignition system and associated spark is important because there were many different manufactur- timing actually work. ers of timers other than Ford and they vary significantly in The authors have been discussing this subject for some mechanical design and construction. The Ford timer case time, each approaching the project with differing objectives. can be usually identified by the word “Ford” in script Steve was interested in optimizing ignition timing for racing stamped into the main case near where the pull lever is purposes and Ron wanted to write an article that would affixed and the roller has similar markings on the spring clearly explain the original Model T ignition system. Our loaded roller support arm, see Figure 2. The timer case has peer reviewers challenged us. It was a convergence of four electrical conductive metal segments mounted in a non- interests and we all had great fun learning the truth about