Here are a few charts from Heinz Heislers book Advanced Engine
 Tech and others. The first chart shows that; as the fuel air ratio gets
 real lean and the pressure lowers in the combustion chamber
 at high altitude the voltage required to fire the plugs goes up.
 Klaus has exploited this situation to lean his engine out
 at high altitude and improve the BSFC to remarkable levels
 by increasing the spark voltage. He has achieved as much as
 100 MPG at 130 MPH and 60 MPG at more reasonable cruising speeds.
 This is a piston engine where the spark plugs are at one end
 of the fire and the piston is at the other end.

    In our case we have a moving combustion chamber where the fire
 travels along side the spark plugs for quite some time. IMHO We want
 the spark plugs to continue to fire for as long as the unburned
 and burning mixture is still present moving past the plugs. That takes
 8.3 ms at six thousand RPM cruise RPM. See chart 2.

 A capacitor discharge ignition system  is very good at firing
 spark plugs fouled with 100 LL but it only fires for .2 ms. Even
 an inductive system (Chevy LS1 coil) or stock Mazda ignition
 only fires for about .8 ms.

    IMHO NO WHERE LONG ENOUGH FOR WHAT WE NEED!

 IMHO we need an ignition system to fire for 8.3 ms or 300 degrees.

 TEN times as long. MSD makes a multiple spark capacitor
 discharge ignition system widely used by Mazda rotary
 engine racers but it only works up to 3000 RPM. After that it
 is "one strong spark" says MSD. Not enough in IMHO. This is why
 I am doing a m.s.d. ignition system with several pre-charged
 capacitors fired in rapid sequence by a cheap single chip computer.
 I hope this is a break through in improving the BSFC of
 the rotary engine. I think it is worth a try.

 Patent applied for :)

 --------------------------------------------------

 This is the range of rotor positions I intend repeatedly firing the spark
 plug. Mostly the leading plug (lower plug) as one does not want to risk
 igniting the mixture in the following chamber.

 Paul Lamar

Good going Paul.  We need the long duration.  Will be very interesting.
Sure wish we access to the Mazda factory development notes and a supply of
the three sparkplug rotor housings the Mazda factory built for the R26B
LeMan's engines to improve efficiency.

Steve Beckham

Paul...  two additional questions popped up on my mind....  1) what are the
specs for the coil now that we've got it flashing a 10x duty cycle?
(capacity or cooling issues?)  2) what are the additional amperage demands
of the alternator? (what is the horsepower drain)

Gary Buster
Tyler, Texas

A capacitor discharge systems is much much easier on the coil
than an inductive system. In an inductive system DC current to the
tune of ten amps flows through the coil on a more or less continuous
basis until the points open briefly to interrupt the flow of current
and cause a spark. Take an old coil and hook it across a battery and
let it sit. This is what happens when you turn the ignition
system on in an old car and don't hit the starter. Careful, don't
touch it. It will burn your hand. In modern cars the time the coil
is on is controlled by the computer and that is called the dwell time.

Tracy was blowing Chev LS1 coils all over the place until he got
the dwell time just right. Never the less the Chev LS1 coils
are designed to be used at half the RPM Tracy is using them.
A piston engine cylinder fires half as often as a rotor.
Once every other revolution of the crank shaft. That is why
I recommend  RX8 coils or 2nd or 3rd gen Mazda coils. They
are designed for a rotary.

In a capacitor discharge system the coil is used in an entirely
different way. It is used as a pulse transformer. The current spike
flows through the coil for only two tenths of a thousandths of a second.
Take a look at a coil on a capacitor discharge outboard motor ignition.
It is tiny!

http://www.google.com/products?hl=en&q=Outboard+motor+ignition+coils&um=1&ie=UTF-8&ei=WF3KSdSxNo_mnQfzufSTAw&sa=X&oi=product_result_group&resnum=1&ct=title

Paul Lamar