On Thu, 25 Jun 1998, Les Myer wrote:
> ................................................... I might even
> take the next logical step and say that I suspect development for
> electronic ignition systems in general was prompted purely by the need to
> meet emissions standards on leaner-burning engines that were more demanding
> on the ignition system - the "timing" of their development (mid-70's and
> later) was right for this - pun intended! :-)
>
I'd have to differ on this part of the historical perspective. High
voltage semiconductor switching was just not feasible (or reliable)
in earlier decades. The vacuum tubes exited your television set around
the same time (and for similar reasons).
I'm sure the evolution of electronic ignition was strongly
influenced by emission control regulations but not purely so. My guess is
that ease of assembly and removal of one "tuning" step reduces labor
costs (that is certainly the big motivator in going from mechanical flight
instruments to electronic displays).
Internal combustion engines are conglomerations of design compromises.
Just because no fuel is perfect, no material is perfect and operating
conditions vary wildly. Les describes a textbook example in the high
energy ignition system where the delivery system with adequate insulation
was too expensive with regard to the benefit gained (until miracle
insulator XYZ is invented :-) But, clearly there must have been a
benefit. (even if it was to allow sloppiness elsewhere). I guess you
don't need any bigger spark than you need but a bigger spark can't hurt.
Hey, anybody ever convert a Spridget to fuel injection?
>
> Where's an engineer when you need one :-)
Well, I don't know. No one has ever said they needed one of us before!
Probably because we usually blurt out long-winded, uninvited opinions well
before someone asks! ;-)
Jim
(Don't know much about history, da-dum, don't know much biologeeeee...)
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