CD ignition what? (kinda long)

From: JCALLENDS (JCALLENDS@AOL.COM)
Date: Wed Mar 18 1998 - 12:57:35 EST


and I agree with most of what he said but I want to comment on a couple of
items.
    From the time that cars quit using sparking boxes like the Model T coil,
our ignition systems have been of the capacitor discharge type where a
capacitor is charged when a switch is closed, points in older cars and Hall
effect transisters in newer ones, and discharged through a coil (transformer)
when the points are opened. This is true for lawn mowers, boats, cars, 4 cyle
& 2 cycle engines and just about any other ignition engine you can think of.
The name CD, for these improved systems, is a bad one. It would be much more
accurate to call them "Solid State" systems. The old systems were limited in
how much electricity could be stored in a capacitor by how long the points
were closed and it was less for a six cylinder engine than a four and even
less for an eight than a six. The solid state system doesn't need to see an
external switch close before it starts to build up a charge. It does it
internally with electronics, and generates a heck of a charge.
    When Uncle Sam started dictating to the car manufacturers some years ago
about emissions the first thing they hollared about was too much gas going out
the tailpipe, and it was true, what with gas selling for 30 to 40 cents a
gallon and a rich mixture being very forgiving on engine parts, no one ever
considered running lean. As you probably know ole Uncle usually gets what he
wants and the manufacturers had to lean out their engines. Now Nicholas
alludes to CD ignitions liking lean mixtures. Lean mixtures are very hard to
ignite, as are certain rich mixtures. Gasoline as well as a lot of other
combustibles will only burn when a certain range of air (oxygen) and gas
exists. If the ratio gets to rich it won't burn, flooding in the engine, and
if it gets too lean it wont burn. It is when we are almost to that no burn
lean mixture that most cars are set up for. After years of trying a lot of
different set-ups inlcluding one called a statified charge that used two
connected combustion chambers the manufacturers figured out that if the spark
was powerful enough they could ignite any lean mixture that would burn.
Nicholas says CD's like lean mixtures, I think it's the other way around, lean
mixtures like powerful spark systems.

Jack Collins Olde4r than old.........87 DAK LE with 225,000+
miles.------98 DAK SLT CC with 4,000+ miles.



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