This might be a question for Lynn, Ed and Tracy. I am trying to get 
togeather the motor controls for my 20 B. This question
would be good for all rotaries though. Do you fire the ignition 
using the "rotary split" or fire all the plugs at once? I jave
been advised by some people who should know that the split 
between plugs isn't needed. Just fire both at the same time. Lynn do
you time the firings on the car? Ed and Tracy, same time or sequential?

  I haven't heard the "answer" on this one when using our new 
engine management systems. I don't believe that I can run a split
on the 20 B using Tracy's system. (but I might be wrong on that) 
Using the Expensive (capital E) Motek or EFI engine management
system I can only run a split  with a system designed for a 
complex 6 or 12 cylinder engine.
Any comments on this one guys?
Thanks, Bill Jepson

Mazda varies it over a 15 degree spread based on a lot of reasons
not the least of which is smog considerations. In fact in some cases one
plug is not fired at all as I recall.  Generally speaking the flame
propagation speed is higher and fuel consumption less when the leading 
plug fires later by around ten degrees. I.E. Trailing 20 degrees BTDC 
Leading side 30 degrees BTDC. In the four rotor 3 plugs were used
with a 3% improvement in  BSFC.

 
 
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