Paul,MSD ignitions were available in the early 70's just expensive. One of the reasons MSD was used WAS the super short spark duration of CDI. The fix since CDI has such a fast rise time and available voltage was running larger plug gaps to insure the ignition of the charge. Spark durration remains a bugaboo to this day. Current coil technology (ferrofluidic cores) allows very small coils with EI to provide excellent energy at the plugs without a huge draw. Most of the newer multi coil ignitions use this to their advantage. The Saab Turbo 4cyl was one of the first to use the technology. The Saab even used a current sensor in the ign to monitor in cylinder conditions, a neat package, and not as power hungry as the MSD systems. I'm not sure if the LS-1 coils are this type. We really have an abundance of riches for ign components right now. I know that MSD is a good system, but for our needs it is rather expensive and heavy to get redundancy. Power consumption is also an issue. Running

a total loss battery EI in racing conditions my 1994 FZR 1000 Yamaha would run a full four hour race on a single motorcycle battery. We always kept a spare but never had to change. High RPMs (12000 max) avrage of about 8000 single ignition. Conditions would be similar to a lead or trailing set of plugs for rotary use. The MSD will probably show a small HP improvement on the dyno, but unless it's a lot, in an aircraft the improvement would be lost to charging the battery, and carrying the higher weight of the ignition boxes wiring etc. Bill Jepson

You keep talking about "power hungary". Are you getting these attachments?
They are less than half the power at 4000 RPM than a stock solid state
inductive system! 

Once and for all.... CD systems now USE less power not more!!!!

The rapid rise time of the spark is WHY they can punch through fouling
deposits!

At high RPM (above 3000 RPM) the single CD pulse is 
just the right width and no more! Why have a spark that last 100
MS when combustion is all over in 5 MS!

Paul Lamar
 
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