> > Wouldn't a super-hot, long-reaching spark jumping a big plug gap have
> some of
> > the same effect as an MSD ignition? People swear by those things, but
> they
> > wouldn't do any good at all if the first spark ALWAYS fired off the
> mixture,
> > would they? If one spark will do, how do "multiple" ones help?
>
> You are right, of course. If the first spark ALWAYS fired the mixture,
> there would be no advantage to an MSD ignition. Once the fuel starts
> burning, it does not burn better from being excited again.
>
> The real problem is in determining "adequate." An old or worn out
> ignition may not provide optimum performance. Very high compression
> ration also require more voltage for an adequate spark. Most of the
> people that I know that swear by MSD ignitions had either super high
> compression or an old worn out ignition. I do not know anybody who had a
> satisfactory running car who said it ran better with an MSD ignition.
>
> When the old distributor wears out, the wobble in the shaft and play in
> the advance mechanism cause some very vague timing and dwell situations.
> Most often it is this that is noticed rather than an inadequate spark
> (though the shifting dwell angle caused by a worn shaft can affect the
> "adequacy" of the spark at high RPM). Just the replacing of the
> distributor with a new one rather than the spark enhancing properties of
> the MSD ignition is responsible for the improvement in performance.
>
> > The selfish reason I'm asking is that my car has a Jacobs computerized
> MSD
> > ignition module and coil, which triggers from the points, and I'm
> thinking
> > about disconnecting it all and going back to the regular coil (which is
> still
> > waiting patiently on the fenderwell). The engine's all racey and
> built, but
> > I don't plan on running the thing at 7000 rpm all day long, and would
> rather
> > have a simple ignition system than that 15-wire mysterious pair of
> aluminum
> > boxes sitting under the hood, which if they break I have no way of
> diagnosing
> > them; I can handle a Lucas coil and points. Any advice??
>
> It has been my experience that if: a. The ignition system is in good
> condition, b. compression is less than 11:1, and c. RPM is around 7,000 or
> less the stock ignition system is more than adequate. When these cars
> were new you did not hear many people clamoring for a better ignition
> system.
>
> Good luck,
>
> Gerry
>
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