Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
In all the automotive literature (at least that I have read) there isn't a single hint to this. But... I am always eager to learn. Tell me where I can find it (internet fora excluded) and I will have a look at it. From what I know a 10kΩ dissipates more energy into heat than for instance a 5kΩ resistor. In spite of having asked around multiple times, nobody so far has delivered any proof for this 'lengthening' of the spark duration.
Reading this thread had got me wondering if my HT caps are within spec. I need to have a measuring session.