This subject came up with Alex and my visit to Tracy's place.

I think we are barking up the wrong tree expecting a four stroke
car coil to work with the rotary AC engine. When it comes to
ignition the rotary is miles closer to a two stroke 2 cylinder
engine. Any given rotor fires once per rev rather than once every
other rev as happens in a four stroke piston engine.

This affects the magnetic design of the coil as there is less time
available to charge it. The Mazda coil needs to charge and fire in
just a few ms at 7500 RPM while an Chevy LS1 coil has twice the time
in a V8. This is a heating issue in the coil.

The design is fundamentally different.

I have not discovered what coil Speed Source is using in their
3 rotor racing engine that turns to 10,000 RPM in a 24 hour race.

Here is the stuff on the RX8 coil failures.

If you get this Tracy hit reply and type OK :)

Paul Lamar


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

Sorry about the large size of that last message.
A real big JPG snuck in there :)

I normally check jpgs for size and cut them down if they are too large using gimp on Linux.

If you did not get it, I can send it again but much smaller.

Here are three more (small ones) :)

Tracy may not have got this as he is out in the boonies without high speed internet. Only 4G as I understand it. My
T-Mobil cell phone does not work
within many miles of Tracy's house :)

4G may take an hour to download that message.

Paul Lamar



Paul,

This is the latest best coil for boosted rotaries. It is a Mercury Marine Coil re-badged by AEM. It includes built in
heat-sinks.


http://rotarycarclub.com/rotary_forum/showthread.php?t=17088

Barry

Nice that they are 2 cycle.
Nice that they have a built in heat sink.

The question is: will they run to 9,000 RPM ?
I don't think so. The good thing about the 2nd gen RX8 coils is
they only cost $25 each.

I am sure the Mercury coil would work better than LS1 coils or any
other GM coil for that matter.

Note:
"Dwell times will need to be adjusted to take full advantage of these coils. PowerFC users will need a dagalogit to make dwell time adjustments."


Tracy is using a 2.5 ms dwell time on the RX8 coils.

That implies they are using a longer dwell time because they can.
They are only running at 6500 RPM or so.

We take off at 7500 RPM.

Dwell time is everything and keeping the coil cool at sustained
high RPM.

Paul Lamar


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