Basic guide to good timing

Tune-ups are one area where you can really feel the difference in performance, especially when the job is well done. And no step is more important to a good tune-up then setting basic (or initial) timing.

Engineers at Champion Spark Plug Company have outlined basic timing procedures that help give maximum engine performance and economy of operation. Champion also warns that overadvanced timing can lead to shortened spark plug life, preignition or detonation, especially if fuel octane is too low for the additional advance.

In order to assure accuracy of your timing, here are some basics:

1. Aim your timing light like a pistol and look straight down the beam of light to the timing mark. Sighting at an angle to the beam, you are likely to be off several degrees when lining up the pointer with the timing mark.
2. Follow printed instructions faithfully. If the chart calls for 850 rpm with the vacuum line disconnected and taped. . . then do it. Many pros remove the vacuum line on all distributors when setting timing.
3. In checking mechanical advance, watch the timing marks while gradually increasing rpm to 2000. Timing marks should advance smoothly. More than 3 degrees of flutter is a sign that distributor needs repair.
4. In checking vacuum advance, with vacuum line connected and engine running, prod the throttle open and closed without changing engine speed. If the vacuum advance is working, the timing marks should shift rapidly.
5. After timing is set from No. 1 cylinder, connect the timing light to the alternate firing plug. Find the alternate by placing half the firing order over the remaining half. (The alternate plug is under number one.) In this case, No. 6 is the alternate cylinder and if there is no excessive cylinderto-cylinder variation, the timing marks will line up the same as number one. More than 3 degrees variation indicates a distributor cam problem.
6. Also remember that breaker point spacing and dwell affect ignition timing. Any time you change point spacing or dwell, be sure to check
   timing.

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