Uncle Jack:
I'm not familiar with this particular unit, but am familiar with multi-spark
ignitions. I formerly designed electronic ignitions 20 years ago when I
worked for Motorola.
First, electronics ignitions cannot produce horsepower. They can only assist
in realizing maximum efficiency and thus horsepower from an engine. The
reason that ignitions seem to produce horsepower is by ensuring that the
mixture
in the cylinder is fully ignited during the ignition cycle. This is highly
dependent on the intake, piston, valve, and cylinder head design and condition.
High gas velocities and swirl that occurs in the cylinder can actually blow
out the fire in the cylinder. A multi-spark ignition has proven effective in
re-lighting the fire in some circumstances. But again, this is specific to a
particular engine design and condition. It may provide no additional benefit
in
cases where the fire stays lit.
The most effective way of lighting the fire, particularly in a lean burning
situation is a high energy spark. Spark energy is spark voltage times spark
current times spark time, all of which are dynamic variables during the spark
event. Inductive storage systems typically provide the highest energy sparks
(Magnetos are higher, but that's a different story). Mulitple spark systems
are
a compromise as you must provide several, lower energy sparks in the same
amount of time (at high rpm's, you only have a millisecond or so of useful burn
time). The physics of doing this actually reduces the total energy that gets
to the spark. But, multi-spark systems have shown they are capable of
relighting the unburnt mixture if the spark goes out, thus they can also be
effective.
The best way to test all this is either a controlled condition dyno test, or
a seat of the pants drive that tells you its working.
Regards,
Myles H. Kitchen
1965 Lotus Cortina Mk1 #128
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