[wwest]

Originally Posted by Lorenfb

"I have no idea what your motive is here, but anecdotal evidence shows that MSD ignitions do what they are supposed to do and are reliable."

The technology has no merit! Where are the data?

"The MSD is just another CDI system with less merit than the Bosch CDI."

No foundation whatever for that statement, in fact it is my personal, educated, belief taht the reverse is more true than otherwise.

And just because the lemmings follow the naive,
doesn't lend credibility to a product. There're are a lot of automotive gimmick products that sell and sponsor race teams, e.g. Bardahl, Slick 50, etc.

Additionally, the spark pulse width of 40 microseconds is half of the Bosch CDI
which results in less time to fully facilitate complete fuel charge ignition resulting in
potential mis-fires and greater emissions."

"potential mis-fires"

"And again, that's why all OEM ignitions now use inductive discharge ignitions which provide longer ignition pulse durations than a CDI."

Not the whole story, not nearly. The advantage of the inductive discharge ignition is that the energy needed to produce the spark has already (just) been previously STORED in the inductor, COIL, itsself. In the case of the CDI however the ignition coil must act as a step up transformer, a task for which it was not designed. Due to the inductive reactance of the coil it will take a finite amount of time for the applied primary voltage to build the magnetic field within the coil core high enough to provide >30,000 volts on the secondary.

This, ELI the ICE man, is where the 450 volts vs only 300 volts applied to the primary has such a significant advantage. The inductive delay of the coil is minimized in this way, allowing a much FASTER risetime to the voltage level required to jump the spark gap. On the FLIP side this is also why the spark duration MUST be shortened, otherwise the prolonged high voltage application to the primary would undoubtedly result in premature coil failure.

If you use a MSD because of the multiple sparks, then you must lend some credibility to a potential of an inadequate spark duration necessitating
an additional spark. But too bad the additional sparks of the MSD have little to no effect to resolve the potential problem.

You seem to forget, or neglect, the fact that firing a fouled or partially fouled spark plug is most often overcome by increasing the spark voltage risetime. And by pure chance(??) that is EXACTLY what results from the use of 450 volts sv 300 volts applied to the primary does. The "desired", target, primary current flow level, and thereby the magnetic field within the iron core, reaches the firing voltage level much FASTER.