Ignition only

[Bruce Plecan]

Now, with that said,
If there is any capacitance on the *firing* end, then the spark with fire
and find a ground anywhere (meaning even thru the spark itself) since it is
an AC voltage.  So you can get a shock without any direct ground back to the
battery other then thru the spark itself.  There is a way to test that
theory, but I strongly suggest not too...

Then for grins, it also explains how why, the SAAB stuff works.
If it was a DC spark then one electrode would really wear.
If DIS truely fired both plugs equally all the time they would wear out 2x
as fast, hmm, and with the EPA tuneup reguirements that would be a definite
no no.
Like Yogi says "mazin, what ya see when ya look"
Bruce


From: <don.broadus at exeloncorp.com>
> sounds good to me Dr. Plecan

> > From: Bruce Plecan [SMTP:nacelp at bright.net]
> > It's an EE thing.
> > The spark is A/C so nothing is backwards
> > There is a 50-50 chance on which way the spark lights, and for the first
> > .00000000001 usec (time approximate) does it really matter?.
> > It's the repeated colapsing on the magnetic fields that generate the
> > current
> > to maintain the firing line on a scope.  Once the ion level between the
> > two
> > electrodes drops, the resistnace goes high the coil condenser
oscillations
> > decay, then you can easily see the A/C component of the signal, and
event
> > over, points close signal and the coil starts to saturate again.
> >      If you think of the secondary as A/C things make sense rather then
> > some of the other explainations, floatin around....

> > I have never seen a proper tuned engine show where one side is different
> > from the other on DIS plugs,  there are the same differences with dissys
> > on
> > some engines.  Largely do to other things like the coolant by pass lines
> > being biased toward on side of the other.  On v series engines there is
> > usually one thermostat so one head is always running a tad cooler then
> > the other in this reguard.
> > Bruce
> >    That's how it looks to me,

> > I'm having trouble understanding the concept of firing the second plug
> > > backwards.
> > > After the spark jumps the gap on the first plug, isn't the "path of
> > least
> > > resistance"
> > > going to be head-block-chassis instead of trying to jump the airgap of
> > the
> > > second
> > > plug?? (compressed or otherwise). I'm probably missing something basic
> > here.
> > > Rod

> > > >0ne difference I didn't see mentioned is that waste spark systems
> > > >fire one plug "backwards". (Normally the hot center electrode is
> > > >negative, since it's electrons being emitted that actually start
> > > >things off, as in vaccum tubes.) This probably means that the plug
> > > >gap in those cylinders cannot be as large as in a "forward"
> > > >cylinder, but I'm not sure if this is a meaningful difference or
> > > >not.


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