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208 - what is dwell time - idle vs WOT dwell

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So i noticed in the webinar that idle Rpm had a much higher dwell time than what was at higher rpm. As an engine would spend most of its time at idle and cruising, wouldn’t you want dwell times at these operation points to be lower to reduce heat and extend life of the coils?

I would have thought that at cranking and WOT areas you would have dwell times closer to the saturation point of the coil as the car only operates there for a brief periods and you need more energy at these points (Street car). If there is a reason to run more dwell at idle how far from saturation would you run idle and cruise?

Also, does increasing dwell time at say idle alter the heat rating of the spark plug in any way?

Hello more dwell time is needed at startup that's a given fact, At idle there isn't much heat generated in the coil because it is only doing low rpm so it isn't charging and discharging at the speed it is at say 6000 rpm I use extra dwell at idle to help burn the fuel with a stronger spark and help with keeping plugs from fouling and good throttle response off idle. increasing dwell time does not affect the heat range of the spark plug unless the coil and or dwell time were weak or faulty or not set up incorrectly but it would have had to be a fair way out to alter that.

I had the same thought, and I set up my dwell table that way. The general idea is to not pump heat into the system when it's not needed. And maybe some components can cool more quickly at idle in between runs.

At full load I give it full dwell, and at low load I reduce the dwell, about .5ms less. And so far it's been working great. Does it actually accomplish the goal of reducing heat of components? I have no idea, haven't actually measured anything. But as long as its working, I see no reason to change it.

Extra dwell during and after startup makes sense, I think I'll add that as well.

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