Opinions wanted ( analysis of the effects of spark advance variation on vacuum)

[Bruce]

>From what I can tell in real world testing the bigger the gap the better.
Trouble is that there is a practical limit.  Some have said the ideal airgap
should be about .1", or use a dispersion type ignition (meaning able to
light the whole chamber at once).  Either one takes a ton of engery to do.

As a practical matter, using conventional ignition components, .035" just
seems to be a good average place to work from.  Even going to .040" drives
the primary voltage to a high enough number that wires, just dont last very
long.

Multisparks are just a cover for not having enough current the first time
around to guarantee ignition, IMO.  The fast build up will help, like in a
cold start, but that's the only place I found any improvement over an
optimised oem set up.  Yes the multisparks are sometimes better then the
oems, but often is a matter that the oem was lacking to start with.  The
best ignition system currently available is a Coil Near Plug, least as far
as I can tell (The FUEL, eDIST seems like a real good idea, I have one here
but still collecting coils for using it).

There are so many side issues also.
Like in the 8051 system just tested, it uses an OptiSpark.  Well that just
so happens to have the largest stock, cap/ rotor air gap that I've ever
seen.  What that means is that air gap sets the min firing voltage, but also
reduces the available spark energy at the plug end.  Hard to foul that
system in the worst of cold start conditions, but sure is tough on parts.
Also, look at the failure rate.

Spark in itself is as much a science as all the other stuff wrapped
together.
Bruce





> I am glad you brought that up.  I used to think that once the fuel was
> ignited, it mattered very little what the gap was or how much energy there
> was in the spark.  After reading Dr. Jacobs book on ignition, I see his
> opinion is very different, but if every thing that I read in that book was
> true, then most cars would be running around with a lot more miss-fires
> than the seem to.
> So what is the effect of gap, big whopping sparks and multiple sparks
> compared to just a stock spark at the right time?
> Ron Schroeder


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