Can you lay out a simple schematic of the ADIS-4 firing two separate
  coils?
  One for the front rotor and one for the rear rotor.
  I was thinking the ADIS-4 #10 pin fired one coil and the  front rotor
 and
  the #12 pin firing the other coil for the rear rotor, I am confused by
 the
  12 volt power supply wire, through the #8 pin, going directly to the
 dual
  coils.
  I am using a separate ADIS for the trailing plugs and all four coils
 that
  came with the Renesis engine so I won't have a wasted spark.


  --
  Karibian


  A 4 cyl EDIS won't work IMHO.
  It uses two waste spark coil packs to handle four spark plugs.
  Using a waste spark on the trailing plugs is not allowed
  so you are one coil short.

  An 8 cylinder EDIS system on the other hand uses four waste spark
  coil packs (four single coils) So you can use two stand alone coils
  for the the trailing plugs and one waste coil pack for the leading
  plugs I think but I would check it on a bench test set up before I
  put it on a rotary engine. It is also possible to use four stand
  alone coils with the 8 cylinder version which is what I recommend.

  Which EDIS system do you have? You will also have to find
  a Ford EDIS trigger wheel.
  http://www.megamanual.com/ms2/36-1.htm

  This pdf covers the whole thing for a piston engine.

  Paul Lamar

  Paul,  The EDIS 8 fires every 90 degrees of shaft rotation so only half
 the
  outputs are usable on an engine firing at 180 degree intervals.  The
 hall
  effect sensor is mounted about 52 degees befor the ignition point and if
  hooked up to the EEC 4 or 5 computer backs up the timing for advance.
  Without an input from an EEC 4 the coils fire 52 degrees of teeth on the
  trigger wheel from where the hall effect sensor is mounted.   If I
  understand Karibian in his post he wants to use two EDIS 4  modules each
  firing two plugs at 180 degree intervals. If there are two hall effect
  sensors 180 degrees apart around the trigger wheel (18 teeth) each
 firing
  an
  EDIS module there are four independant sparks at 180 degrees. If the
 second
  Hall effect is retarded 1 tooth it will fire the trailing plugs 10
 degrees
  different than the leading plugs. Leaving the 18 tooth separation and
  firing
  leading and trailing plugs at the same rotation provides a completely
  redundant ignition system.
       The EDIS is a waste spark system meaning that the spark energy goes
  to the cylinder with least pressure fires that plug goes thru the engine
  block and fires the second plug on the circuit back to the coil.  If
 only
  one plug is connected to the coil pack a path to complete the circuit
 brom
  the block  back to the other terminal on the waste spark coil must be
  provided.Firing only one plug will dramatically increase dwell on the
 plug.
    The EDIS  and Hall effect sensor are really light, inexpensive even if
  new parts are used so using two of them doesn't seem to be a problem.
 The
  parts are encapsulated in a plastic block so moisture, vibration, and
 low
  air density should not effect their reliability. Using two 4 cylinder
 coil
  packs does add weight but until someone weighs two of them as compared
 to
  four single plug coils the difference in weight is unknown.  Using the 4
  tower coil packs that came with the EDIS would match the electrical
  resistance and inductance of the EDIS and coilpacks as Ford designed
 them
  and would be expected to be as reliable as the car ignition. My piece of
  mind is worth a few ounce weight penalty using the waste spark coils.
 The
  coil pack is actually only two coils molded together with a tower
  connection
  of both ends of each of the two coils for a total of four plug
 connections.
  Two coilpacks is a total of four coils just like four individual coils
 just
  less mounting brackets to fabricate.

  george grimes

  I was afraid of something like that. Do you have a chart of
  a Ford V8 showing when each cylinder fires as a function of
  the crank angle? I have the firing order. Is the Ford a single
  plane crank or 90 degree crank? Must be a 90 degree crank if
  it fires every 90 degrees. Too bad I thought I was on to something.

  I guess you will need two 4 cylinder EDIS. With a little
  fooling around I think I can get one CAS to fire two
  units. Those are mag sensors and not Hall Effect.
  Hall effect require rotating magnets. Ford calls them
  "Variable Reluctance".

  I would not use the waste spark coil pack on the leading
  plugs with just one plug. I am not sure
  why. Have you tried it with out a spark plug load?
  I dimly remember from way in the past that could be
  a no no. Perhaps it arcs over inside the tower.


  Paul Lamar


 Paul,  It fires an EDIS 8 every 90 degrees just like when it had a
 distributor cap.  It fires one coil pack every 9 teeth on a 36 tooth
 wheel.
 Using the waste spark coils fires the 4 cylinders on the second
 revolution
 using the same four outputs. Using a 27 tooth wheel with an EDIS 8  there
 would be three outputs 120 degrees apart (still counting 9 teeth) and the
 missing tooth would reset the count not firing the fourth output'. I
 haven't
 tested this three rotor idea but IMHO that is how it works based on two
 weeks of Internet research.
          Personally for the return circuit back to the waste spark coil I
 suspect a resistor would be required in series with the plug lead. I am
 intending to just screw some extra spark plugs into a block of aluminum
 bolted to the block which won't fire anything just provide the electrical
 load. For the four rotor there is a small pad on the connector bell
 housing
 between the engine sections thick enough to screw the plugs into which
 was
 necessitated to be able to remove the pattern from the casting sand
        You are right they are actually variable reluctance coils not Hall
 effect. I am going with two of them so that I can fire the plugs
 separated
 by a few degrees of E-shaft rotation and to make each half of the
 ignition
 completely independent.  This is also a multi-spark ignition at the lower
 RPM
 of the car engine but resorts to single spark at high RPM with an upper
 continuous RPM of 8000 RPM
       With no moving parts and the reliability and price of well
 developed
 mass production  parts I just don't see any downside to this stand alone
 ignition. Ford liked it enough to build 12 million of them before
 incorporating it into the engine computer.

 george grimes

 Upload a schematic for Hurant.

 Paul Lamar

 George...

 I am not certain that the current path you described above is correct. I
 have always read that the wasted spark was really not a full spark due to
 the much lower pressure and conductivity of the combustion atmosphere
 compared to the cylinder that is loaded with fuel and air. The current is
 simply looking for the least resistant path, and the charged cylinder is
 it.
 Therefor, of the two possible outlets of each coil, the one with the
 lowest
 resistance at the point of arc, releases the load.

 Correct me if I am wrong

 Ed Carver

 Here is the way I think it works.

 Air is an insulator. Higher pressure better insulator.
 Higher resistance. High altitude magneto's must be
 pressurized.

 Power = voltage times current. The waste spark is looking
 at a comparatively low pressure low resistance chamber. Almost a short.
 There is no voltage across a short. So no power is dissipated but
 the spark jumps easily.

 So the compressed mixture gets most of the spark POWER.

 One might try grounding the un used spark tower.

 Paul Lamar Leesburg VA

 If the coils could handle it the ford edis 4cyl would be ideal for the
 2 rotor. Each coil fires It's two plugs every 360 degrees. And the
 coils fire 180 degrees apart.
 The edis coils can't handle two sparks under pressure.
 The edis coils do not have igniters built in. LS1 coils do. So you
 could remove the edis coil and fire four ls1 coils. It would take a
 big resistor between the edis module and the coils. LS1 coils fire on
 a 5v signal.
 Blake
 --
 Blake C. Lewis


Have been following this thread for a while. However, with having only one
rotor to fire in the single rotor, I had not much to contribute. There is
an
exception with something I ran into. Using a coil with a build in igniter
like an LS1 or RX8 coil the following need to be considered. These coils
are
unsuitable for using with a direct CAS trigger. The 5V signal need to be
appr. 2ms long, and the spark occures at the end of this pulse, resulting
in
a constant 2ms delay of the timing. This can only be accounted for with an
ECU.
I am using on the single rotor a Street Fire CDI,  firing a single waste
spark coil from an older GM.
FWIW.

Richard Sohn
N2071U
 --
Thanks Richard. That aswered the questions I had on those type
of inductive ignition systems. I suspected as much. I won't
waste any further effort with them. I suspect this may be the
cause of some of Marks S ignition problems. However any CD
system can be  fired when needed as long as there is enough
time to charge the cap.

The EDIS on the other hand has the ECU built in.
And that is why it needs to be set 10 degrees ahead.
It may not work at 7500 RPM.

If one is thinking of using it one better test it with
the Ford trigger wheel mounted on a high RPM electric
motor.

Paul Lamar

Bill and Blake,  The idea of using the EDIS-4 and the four tower coilpack
with one coil hooked to the two plugs on rotor one and the other coil hooked
to rotor two is obviously workable. In the event the coil has difficulty
firing two plugs under compression the gap of the spark plugs could be
reduced slightly. I just can't advocate not having a redundant ignition on
an aircraft. With the dual system one on leading and one on trailing the
loss  of any one coil or plug wire coming off the engine still fires both
rotors. Also the leading and trailing plugs don't necessairly have to be
fired at the same time although they could be.

      Mixing igniter coils on the Ford ignition controller is just bad on
so many levels. The EDIS controller does not use a 10 degree offset it is
more like 5 teeth on a 36 tooth wheel. To vary the timing a SAW (spark angle
width) count is sent by the EEC-4 or EEC-5 engine controller and the EDIS
counts down to the first spark of the rotation. This reverts to the standard
fixed advance if no signal is received for two revolutions. After EEC-5 the
EDIS is incorporated into the engine controller rather than being a stand
alone system. In either case the RPM limit is 8200 rpm.   Ford used this
ignition on some of their factory sponsored race cars which did not operate
over 8000 RPM and it is currently used by Megasquirt on their after market
fuel injection.

    If I were tempted to mis apply an EDIS, I would probably  use it with a
555 timer to make a PWM sequential fuel injection.

george grimes