What is total timing, and how do I set it on my engine?
Total timing, which refers to the maximum amount of ignition timing applied to the engine, is easy enough to calculate. You get the number by adding initial timing to mechanical advance. Correctly setting it, however, involves multiple steps.
First, you’ll want to determine your desired total timing. Every engine will run a little bit differently, and the ideal number for yours depends on multiple factors.
The tables below give some general guidelines. However, you will need to test and tune to determine the best setting for you.
|Engine Type||Total Timing Starting Point|
|Naturally Aspirated||34 – 36 degrees BTDC|
|Forced Induction/Nitrous||28 – 32 degrees BTDC|
|Factor||Advance Timing For:||Retard Timing For:|
|Ignition System Power||Low||High|
|Fuel Octane Rating||High||Low|
|Combustion Chamber Design||Open||Compact|
|Spark Plug Location||Offset||Center|
Rev the engine past the point where your mechanical advance is fully engaged. Usually, 3,000 to 3,500 rpm will do it. Pay attention to the timing mark on the harmonic balancer using the timing light.
Rotate the distributor until the timing mark lines up at zero with the light. Tighten down your distributor and you are done.