If you firing a rotary engine six times every 10 degrees at 10,000
RPM you need a fast crank angle sensor.

This has a rise and fall times of about 20 nano seconds. A nanosec is
one one thousandth of a micro second. Of course everybody knows a
micro second is one one millionth of a second.

Consequently a nano second is a short period of time to say the
least.

Naturally I am very pleased with this device. It is molded plastic
and strong as brick. I'll be sending it off on Monday to Poul
Woelflein Germany so he can mount it on the e-shaft of an AIXRO kart
rotary  for testing our new patent pending high speed CD ignition in
a week or two.

It has the promise of reducing the fuel consumption, increasing the
power, reducing hydro carbon emissions and curing an occasional
mis-fire at idle due to port overlap. It is six times more likely to
fire a bad mixture.

The pulse width shown is about one millisecond and the pulse
amplitude is zero to 12 volts. A very solid and unambiguous signal.


Paul Lamar

Hi Paul,  The ignition looks very good.  Could you mention my name
to Poul.  I am gathering info for a magazine article and may need
some information from him.  Any news on Austro Engines new 80 hp
rotary. There was a bit of info at the beginning of the year but
now, nothing. Murry

I think they may have ran into problems. I suspect they
underestimated the torque pulse from a one rotor that large. I don't
really know. Seemed like a good idea at the time. I think they would
be better off with a turbo as their main customer is Alexander
Schleicher sail planes, the worlds largest user of rotary engines in
aircraft not counting UAV's.

Ignition of gasoline depends on the spark being immersed in a
mixture in the air fuel range of 10:1 to 20:1. The mixture ratio
varies widely in the combustion chamber and it is very turbulent
meaning that any given moment the mixture may or may not not be
ignitable. Due to port overlap some exhaust gases (less oxygen) could
be included making the mixture non ignitable at a given moment in
time.

That is what happens in the old Mazda 13B and causes a distinctive
and noticeable miss at idle. The RX8 eliminated the port overlap for
that reason.

This ignition is six times more likely to find an ignitable mixture
ratio because it waits for a good mixture to come along :) Notice
the Wankel combustion stroke lasts almost 300 degrees while the
piston combustion stroke is only about 120 degrees. During this long
time period some un-combusted combustible mixture may be passing the
spark plug. We know this is the case because of the high hydro
carbon content in the Wankel exhaust. Our goal is to ignite that
mixture thereby gaining a lower BSFC and more power.

It is well known that a hotter spark can ignite a lean mixture
better. The best MPG in an aircraft engine is obtained with a lean
mixture in the vicinity of 18:1 and with a spark advance of 50
degrees or so at low manifold pressures (high altitude).

I am counting on that happening with this ignition.

Klaus tells me a good ignition can set paper on fire. Mine has no
trouble doing that :)

Paul Lamar

If it were not for airplane use, I'd add a Reed-Valve close to the
rectangular intake port opening in the working housing surface, as
per the patents US3844256 Nissan, 1974, US1412931 and US4020800
Nissan, 1974; US3514235, Yamauchi, Yanmar Diesel, 1970, or CA1032477,
1978, and CA1045553, 1979, both by Ford; and if somebody has a
housing in its last days of useful life, I'd suggest testing the
results of the patent US3848574  by Kawasaki, 1974.
Dreamin' is free! Thanks for your attention. Best regards. Salut †
Jose Gros-Aymerich; Madrid, Spain

Jose, forget reed valves. They are a HP penalty. What does the same
thing is mounting the slide throttle close to the p-port. NSU knew
this way back in the 60's.

Paul Lamar
       Thanks, both Suzuki in their RE-5 and Norton in their Commando
     air cooled two rotor engine used the approach of putting the
     throttle disk close to the port opening in the housing working surface,
    the peripheral port in the OMC Snowmobile engines, that opened only
    after a third of the accelerator cable course was reached, (A bit the same,
     but the opposite action, as the cable or intake manifold depression controlled
      'bypass' port in the Aixro and Sachs KC-27 engines), was installed
    the same way.
     Yes this, this will reduce a bit top rpm power output,
    but for the use I like, street cars, it can have some advantages.
         I attach the R-V chart from Yanmar Diesel, I'm not sure of having send
     it before, you can see more in the Reed-valve discussion in aaroncake.net
     RX-7 'General stuff', discussions older than 6 months.
           If I finally manage testing this, I'll let you know the results.
     By the way: I read yesterday that if you pre-heat the cooling liquid
     and thus the engine, before starting it, functioning is improved, and
    thermal distortions reduced. Anybody having experienced with this?
      Hope it's useful for someone. Thanks a lot. Best regards. Salud †
            Jose Gros-Aymerich
         Madrid, Spain

     The 2nd image comes from SAE paper 890325, Tatsuya Kita, Mazda
       'Noise and vibration reduction technology for Rotary Engine',
      in SAE 1989, SP-768: 'Rotary Engine design: Analysis and developments'
    the others are images in the book 'The Wankel Engine, design and performance',
     by R F Ansdale, London, 1968, ISBN 0 592 00625 5



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