LX9 crank relcutor - Megasquirt - Coil near plug

[Jonpro03]

I've already bought and installed the 7x external crank trigger. I did this because I thought that the Megasquirt wasn't able to read the 'odd' crank reluctor on the LX9. The downside of doing this was that I had to use a 3100 DIS ignition complete with ICM. If I can get the megasquirt to understand the crank reluctor, I can set the megasquirt up to use the coil near plug (CNP) setup that the 3500 uses. In other words, the coils are fired directly from the megasquirt. Or, instead of using the 3500 CNP setup (which is not really 'near'), I can use a LS1 CNP setup or better yet, use a COP setup.

To do this, I need the megasquirt to understand the LX9 crank reluctor. I knew the megasquirt supports the LS1 crank reluctor which looks a lot like the LX9 reluctor, but it was my understanding that the LX9 reluctor is 58x whereas the LS1 is 24x. Well today I plotted the LX9 reluctor and then plotted the LS1 reluctor. I used 'A' for long and 'B' for short, and 0 for the forward wheel (in the pictures) and 1 for further. These are my results.


LS1 = A1B0 B1A0 B1A0 B1A0 B1A0 B1A0 A1B0 B1A0 B1A0 B1A0 A1B0 A1B0 B1A0 B1A0 A1B0 A1B0 A1B0 B1A0 A1B0 B1A0 A1B0 A1B0 A1B0 A1B0
LX9 = A1B0 B1A0 B1A0 B1A0 B1A0 B1A0 A1B0 B1A0 B1A0 B1A0 A1B0 A1B0 B1A0 B1A0 A1B0 A1B0 A1B0 B1A0 A1B0 B1A0 A1B0 A1B0 A1B0 A1B0

EDIT: I have rearranged the order so that it matches what the CPS sees. I basically mirrored and reversed the previous. I also started in a different location to match the LS1 configuration for TDC #1 compression.

They are the same.

So my next step is to determine where the wheel is at TDC of cyl 1. Brad, I used your picture of the crank reluctor when I plotted. I noticed you marked the reluctor. Did you mark that TDC cyl1?



Is there anyone who has a LX9 crank laying around that they can determine TDC cyl1 for me?

[bszopi]

I just marked a spot on the trigger wheel and a spot on the crank, with no regard to position.

[Jonpro03]

One of the Megasquirt Extra devs is sending me some code that assumes that TDC #1 compression is at the same spot on both reluctors. I'll be testing it tonight.

[dskopek]

I did not use the 7x wheel, I installed a 36-1 wheel on the back of the harmonic balancer and am using megasquirt to do everything from that.

[Jonpro03]

I did not use the 7x wheel, I installed a 36-1 wheel on the back of the harmonic balancer and am using megasquirt to do everything from that.

Cool. Did you get that wheel from DIYautotune?


I got an email with the LX9 code in it, and a set of directions I'll post here for anybody else who decides to do this swap.

Attached is the updated code, but first, take a deep breath.

Download and load the MS2/Extra 3.1.0 release code as-is.

Be confident it has loaded and you can communicate with it in
TunerStudio.

If you were using a different MS2 code version before it _might_ be
worth getting your engine running on MS2/Extra with your existing GMDIS
setup - so you have a baseline.

Once that is ok and you understand the process, save the attached
ms2_extra.s19 in the place of the one you extracted from the zip file
and go through the firmware loading process again.

You won't need to change any project properties in TunerStudio this time
and it should connect ok.

In the title bar you should see the version as 3.1.+ and today's date.

If that passes ok, then remove power to your coils and injectors.

Load in your settings but this time set the spark mode to "LS1" and
output to wasted spark. Burn, power off, power on.

If you crank the engine, hopefully you will see some rpms and the three
LEDs will flash in sequence.

Next step is to hook up the coils (direct coil control) and strobe the
timing to see if it is anywhere close. The wheel phasing is set the same
as LS1 - you will have to find out if this is the same for the V6.

I can get most of this done tonight, all except the last step. In order to hook up the coils for direct coil control, I need to build 3 circuits on the megasquirt.

First, a modification to the tach input


Then, build a circuit for cam position sensor input


Then the modifications for output directly to the coils. Only need 3 circuits since I'm using waste-spark on a V6. (So no need for SparkD)


To wire it in, the crank position sensor goes to Pin 24. Cam position sensor to Pin 3.

Pin36 for SparkA, Pin4 for SparkB, and Pin5 for SparkC.

[bob442]

http://www.eficonnection.com/eficonnection/58x.aspx

lsx's are 58x reluctors
i suppous we could use a E38 ECM on our motors and just edit out the extra 2 cylinders

[CNCguy]

I have no experience with the LS trigger wheels but assumed they were like the LZ series wheels which are a 60-2 configuration and nowhere similar to the LX9 "digital format" wheel.

[Jonpro03]

The LS1 wheel is definitely not a 58x wheel. It's shown here on the left:

[bob442]

the LS1 Is NOT 58x, it is 24x, a LS3-LS9 Is how ever a 58x

[Superdave]

the stock 3500 trigger wheel is marked with the 7x marks, you should be able to figure it out from there.

[Jonpro03]

Hey look at that!

[bszopi]

the stock 3500 trigger wheel is marked with the 7x marks, you should be able to figure it out from there.

I always wondered what those dimples were for... duh!

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[dskopek]

Cool. Did you get that wheel from DIYautotune?

Yes i did, I removed the stock ring and pressed in a sleeve into the balancer that i mounted the wheel on. This way i have a external trigger that i can adjust very easy.

[Superdave]

I always wondered what those dimples were for... duh!

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I'd double check them VS a TCE trigger or an older crank but logically they should be correct. Those are the marks i was going to use to locate the 7x wheel on the crank when i go to my next build stage.

[bszopi]

I have a CAD drawing of the stock trigger, so I could probably print it out and see if everything aligns.