snips...
It is not that I attached to it. I have a couple. I
would rather do the development so the spark will
work
with 3rd gen and RX8 engines. Also it is easier to
mount the
alternator on the side of the engine if there is no
CAS installed.
Are you referring to the LS1 type coil per plug
module.
Do you have a picture? Is this it?
Paul Lamar ...No rotor no motor.
Paul,
There is someone working on decoding the stock RX8
toothed wheel as well, so that issue may be taken
care
of shortly.
The 4-pin module I refer to does not contain a coil.
All it does is interpret the VR signal from whatever
mag pickup you are using, and fires the coil at the
moment the tooth passes. It predicts when the next
firing event is to take place, and starts charging
the
coil ahead of time, current limiting to around 6-7
amps.
See attached pic. W and G pins go to the VR sensor.
B and G go to the coil to be fired. A single 4-pin
module could be used to fire a twin-post coil on the
leading side. The same is usually not done on the
trailing side due to the chance of prematurely
igniting the mixture in the opposite chamber at
retarding spark angles. I've seen others come up
with
twin 4-pin modules for the trailing side, triggered
appropriately.
More details on the 4-pin here:
http://www.megasquirt.info/HEIgn.htm
That's why I went the EDIS route. It is similar to
the GM 4-pin, but instead decodes a 36-1 wheel, and
provides two spark outputs, one for the front rotor
leading coil, the other for rear rotor leading coil.
A second EDIS module in parallel fires the other two
coils for trailing. This setup could be installed
on
any 2-rotor, with the addition of a toothed wheel
and
VR sensor.
Roger.
Well then as I understand it these GM LS1
one-coil-per-plug
units do not have a problem with charging time and
current
limiting. They fire when they are told with a five
volt
pulse and thats it. I could be wrong. These are the
units most
of us have and most of us are using now. GM part #
12558948
If it takes some signal conditioning so be it.
If necessary I can set one up on the bench as I have
a
pulse generator and 12 volt power supply with
current
monitoring to verify.
Lets keep this simple and deal with only one issue
at
a time. Too confusing otherwise. I am not
considering
the extra code at this time. Just the basic
MEGASQUIRT- 2001- V3.000 code to keep it simple.
That's a good place to start, but you will not be able
to control ignition with the V3.000 code. If you plan
to work out another solution on that front, then this
code will work for fuel only. The only other issue
that comes to mind would be injector staging, which
again is offered only in the -extra code.
For example: I assume the RX8 wheel will be
incorporated
in the extra code so that is of no interest right
now.
Is that a correct statement?
Yes...certainly will not be ported back to V3.00.
We can make a cheap steel disk that will work with
2nd gen,
third gen or RX8 keeping it simple.
Some of us would also like to use MSD units. As I
understand
it these too can be fired with a simple five volt
pulse.
Paul Lamar ...No rotor no motor.
If you want to run LS1 coil packs from -extra code,
then it's pretty straightforward. Like you say, these
units have integral ignitors and take a logic-level
signal, so driving them should be simple.
In the msnsextra code settings for rotary, there is an
option for FC or FD style ignition triggering. You
want FD. Here's the difference:
FC uses a single trigger pulse for leading. The
trailing uses a trigger pulse at the same frequency as
the leading, but some ecu-determined timing offset.
As the two trailings need to fire separately, there is
a third signal, the 'select' signal, which determines
which of the two individual trailing coils to fire.
So...three control signals to the coil packs - leading
signal, trailing signal, and trailing select signal.
FD uses a single trigger pulse for leading as well.
For trailing, each coilpack has it's own dedicated
timing signal, rather than the 'select' method used in
FC.
The rotary code is set up to use the three led
circuits as ignition outputs. Pullup resistors need
to be added as shown in the pic part way down this
page:
http://megasquirt.sourceforge.net/extra/setup-gmdis.html
The two leading coilpacks would be fired together via
one led driver circuit, and the remaining two led's
would fire the two trailing coils.
I realize the MS world is hard to follow. Such is the
nature of a highly active open source community.
Development happens at lightning speed, so newer codes
are feature rich, but often documentation-poor!
Roger.
You are back to talking extra code here. I am not going
to run the extra code. If necessary I can modify the basic
V3 code. There is a lot of stuff in the extra code
we don't need for an aircraft application.
I don't really care about new developments anyway.
They mostly seem to deal with car issues.
Extra code is four or five times larger. Harder
to maintain, harder to debug and harder to modify.
Keep it small and tight. KISS
I am going to fire leading and trailing plugs at the
same time. And if necessary I will fire
them fixed advance. The processor need not be involved.
Lots of options for doing that. We can add our own VR
conditioners for each of two mag pickups on one steel
wheel with one tooth and fire the coils directly. We
can OR the two outputs together for the tach signal
going into the processor.
Also staging is unnecessary as we can run rich
on the low end unlike a car application. An aircraft application
never gets below 5000 RPM and a 130 HP and only goes as high
as 7500 RPM. I am more concerned with getting enough fuel
at 7500 RPM. Tracy has had some strange things happen
when he stages at 15 inches of Hg.
Paul Lamar ...No rotor no motor.
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