Non-LS Application of Gen 3 PCM
Hey guys, first time poster here and am yet to purchase EFI Live. However, I have a current project that I need some input on. I am working on swapping a 4.6L Northstar into a 4th Gen '99 Camaro. I have virtually everything else figured out but the PCM side of things. I would like to run this motor on a Gen 3 LS PCM and ignition coils for the tuning capabilities. As you probably know, the stock Northstar PCMs are not easily tuned. There have been people that made the Northstar run with a LS PCM but using the waste-spark ignition coils which I would rather not do.
The obvious issue is the firing order difference between a Northstar and LS motor. I have read this can be easily remedied by changing pins on the PCM connector and reassigning the cylinders in the tune, similar to what is done with EFI Connection's LT1 system. The Northstar bank assignment is also reversed from typical longitudinal V8s but I think that could be changed in a similar manor and the firing order. Northstar firing order is 1-2-7-3-4-5-6-8.
So I currently have a 0411 PCM, LS1 wiring harness from a 4th gen camaro, and LS ignition coils. The Northstar has a centrally mounted reluctor wheel on the crankshaft with two sensors both placed off of centerline with one reading 27 degrees behind the other. It is technically considered a 24x wheel but looks very different then the LS 24x wheel. This makes me think it won't just read correctly if hooked up. Here is a illustration the Northstar setup:
From my understanding there are 3 options to make this work:
1.) Use the stock Northstar reluctor and crank sensors. Setup the PCM to read this signal and fire the coils and run the injectors. This seems to be the most complex programming wise, however might be possible because the people who have run the Northstar on a LS PCM before with waste spark coils have used the stock reluctor. So it would seem there is a way to change what the PCM looks for in terms of crank signal?
2.) Change the Northstar reluctor out for a a 24x LS wheel. Not sure how this would be physically possible though due to the wheel being in the middle of the crank. This option would involve more physical work but would be easier on the PCM side.
3.) Mount a external 24x wheel and sensor for the PCM to read. Seems like the easiest option at this point but I worry about reliability and it being too rigged.
I have contacted several professionals with this proposition and all have either told me that didn't have time to think about it or gave me the brush off. So I figured asking on a knowledgeable forum would be next best bet. I would like to make this work so any input is appreciated. Thanks for taking the time to read the post.
P.S. I have also thought about the cam sensors, as it is a single pin on the cam gear and not a 180 degree bump like the Gen 3 LS cam reluctor. I haven't come up with a specific solution for this yet but consider it a lower priority then the crank pickup.
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Originally Posted by GMPX
