Matt Rhys-Roberts wrote: > > Could anyone recommend a primer on designing plasma ignition, i.e. > > very high energy spark ignition systems? My idea is to seriously > > improve the tired old ignition system on a 2-cylinder 4-stroke > > motorcycle, and I'd > > like to experimentally create the fiercest spark that's reasonably > > possible. >Olin wrote: >Then maybe you can explain why that matters. Obviously you need a=20 talk of stronger sparks being better, but nobody has ever explained=20 >exactly why. What is the advantage of a stronger spark past reliably=20 >starting combustion? Once some combustion starts, why can't it be=20 >considered the "spark" for further combustion until it runs to=20 >completion? No matter how strong the spark, wouldn't it still only=20 >ignite a small portion of the mixture in the cylinder, which means=20 >it's relying on the combustion chain reaction for most of the burning=20 >regardless of how strong the spark is? Olin, Of interest but perhaps sideways to your question - Once upon a time, a friend was taking me for a ride in a light plane.=20 While still on the ground (I think), he said "watch this" and flipped a=20 switch to engage the second, back up, spark system and the RPMs went up=20 significantly, perhaps as much as 10% (VERY long time ago - not sure of=20 the %). I don't know why, and this may not address your why question=20 anyway as I would guess it creates a second flame front which is=20 different than a longer spark. On the other hand, a bigger, fiercer=20 spark (as apposed to a longer spark) may create a bigger faster flame=20 front. One thing I think I know is that the whole deal inside the combustion=20 process is complicated and may not be amenable to armchair ponderings.=20 But may well satisfactorily yield to experiment. I say "spark on, Matt,=20 let us know what comes of your explorations" --=20 Looking forward, Al Shinn --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .