Kai:
I am going to take exception with the horsepower claim. The
speed of the flame front is strictly limited by the chemistry involved,
and is independent of the energy delivered during the ignition event.
The flame front travels at roughly 100MPH, no matter what you do. If you
could make it travel faster, then ignition advance would not be needed.
Peak cylinder pressure therefore is also independent of spark
energy.
I would be happy to recant in the face of some dyno data, but I
believe that a hot ignition system is more on the order of a preemptive
strike against misfiring, plug fouling, etc and of no advantage in the
power department.
The wider plug gap once again is simply more insurance against
problems, not a power adder.
Let the flaming begin!!!
Cheers,
Vance
-----Original Message-----
From: Kai M. Radicke [mailto:kradicke@wishboneclassics.com]
Sent: March 07, 2005 4:56 PM
To: Navarrette, Vance; 6pack@autox.team.net
Subject: Re: Ignition
<snip>
What? Power output and engine response are not affected by the
intensity of
the delivered spark? That might be true if you do not adjust your plug
gaps
to take advantage of the greater voltage that the high output coils can
deliver. I recommend a .035" gap on cars running with Lucas Sport
Coils,
this is a pretty sizable increase over the stock gap.
The simple fact is, if you have a higher output coil you should be able
to
run a wider plug gap. If you can fire the spark plug across that wider
gap,
the spark that is exposed to the cylinder is larger. A larger spark has
everything to do with the rate that the flame front moves in the
cylinder,
which does have a positive impact on power and engine responsiveness.
Spark
intensity also has some impact on the point that peak cylinder pressure
occurs and peak cylinder pressure itself. Cylinder pressure on the
power
stroke is the sole reason our cars move forward.
<snip>
Kai (who probably just wrote more than anyone cares to know about
ignition
theory)
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