[quote]ORIGINAL: tkg
ORIGINAL: captinjohn
ORIGINAL: av8tor1977
I will say the description how it works is very good. But any ignition that advances the timing with the RPM increasing...is a auto advance ignition. Capt,n
No that is incorrect. An ignition that is an advancer STARTS with the timing around 4-5 deg BTDC. An ignition that is a retarder starts around 30 Deg BTDC and retards the timing at low RPM. As the rpm increases it returns to its starting point. It does not advance, it retards less.
Why don't we just call it Computer Controlled Timing.
Terry,
It is good to know if the ignition is an advancer or a retarder if you consider how to set the timing.
Advancers need to have the timing set at between TDC and 6° BTDC
retarders must have a setting of 20° - 35° BTDC, depending on engine make and application.
Some advancers, like the VLACH and Falcon are/were in fact super retarders. Because the pickup signal came too late to fire the same cycle, the signal time was stored and used to fire the next cycle! If I am informed well, they used the mean of the last 10 cycles to do that. When starting, these were fixed timing ignitions, switching to super retarding when the engine was running.