Ignition timing

Setting the timing on a vehicle is a simple task. First you must know what the manufacturer’s spec is for the stock timing. This information is usually under the vehicle’s hood. Many vehicles have their ignition timing set somewhere between 6 and 12 degrees advanced. Advanced ignition means that the spark that occurs in the cylinder happens earlier before the piston reaches top dead center. After you know what the timing spec needs to be you will need a timing light. Connect the timing light up to the battery or power source that it uses first. Next connect the clamp over the number one spark plug wire, which obviously runs to the #1 cylinder. This should also be marked on your distributor. If your distributor has a vacuum line running to it, remove the vacuum line and plug it so that it doesn’t suck in air. If this line is not plugged, the timing reading can be incorrect as the timing may be advanced slightly. The next thing you will need to do will be to locate the timing mark usually high-lighted yellow on the end of the engine or dampener.

 

When the engine is idling the yellow mark should show up in one spot due to the strobing light. There should be stationary tabs with lines and numbers that will guide you to where the engine’s current timing is. Most newer cars should not be adjusted because the car’s computer will automatically adjust the timing. Older cars timing can be adjusted by loosening the bolt that holds down the distributor. Mark where the distributor is currently rotated to. Then the bolt only needs to be slightly loosened until the distributor can rotate. Rotate the distributor clockwise or following the rotation of the engine to retard the timing. Rotate the distributor counterclockwise or against the engine’s rotation direction to advance the engine’s timing. Small movements can make a considerable difference in timing. Verify the results with the timing light. Some people will advance their ignition timing to try to gain a little top end power, which in some cases may help. Without a dyno you are only guessing and many times will actually hurt the vehicle’s power. Sometimes retarding the timing will be done to reduce the hc’s for emission testing also. There is an ideal spot for the best emissions, don’t retard too far or they will go bad again. Make little changes (1 deg.) to see what happens if you don’t have an emission sampler handy to test with. The stock ignition timing is usually a good compromise between power and low emissions.