Mark Steitle wrote:

Ed,
Thanks for the clear and to-the-point explanation of this.  One thing I didn't mention that sort of bothers me is the life of the spark plugs in a rotary.  I've heard it is rather short compared to other internal combustion engines.  The 20-40% loss of power could make a significant difference in how your day goes.  The chance of both leading and trailing plugs quitting at the same time is obviously much less.  I guess the 10-15 degrees of timing lag wouldn't make a hugh difference in power output.  I may go ahead and use the six separate LT-1 coils, rather than three twin-tower GM coils for my 20b.  If they really only weigh 5-6 oz. each, there isn't much of a weight penalty, if any.
Thanks for your input, Mark Steitle

No big deal at 50 hours a year you just change the spark plugs every four years.
Tracy tried running them forever :-)

Mazda plugs are real cheap compared to AC plugs. Try buying twelve AC plugs
for an O-470. 

Paul Lamar
 
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