Thread: LB7=LMM Swap
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Old 09-23-2014, 02:04 PM
duratothemax's Avatar
duratothemax duratothemax is offline
<--- slippery roads
Join Date: Aug 2006
Location: Wyoming
Posts: 7,836

Bumping this up....

Im doing a standalone harness for a customer, and he has an LMM engine. Its 100x easier to do standalone with 2001-2007 ECM OS's because cruise control and speedo/tach are configured as discrete signals on the older trucks, as opposed to just being sent as data messages over GMLAN on 2007.5+ trucks.

So Im suggesting the guy buy an LBZ ECM, plug it into his LMM harness (there are a couple minor pin differences, Ill worry about that when I build the harness), and run the LMM as an LBZ.

Its been years (probably 7 years) since I messed around with LBZ/LMM "hybrid" tunes. IIRC the pulsewidth and timing tables were a little different but thats about it. So if I just use LMM pulsewidth/timing tables as a start, copy-pasta them into the LBZ there any reason an LBZ ECM wont happily run an LMM (injectors)??

Ill probably just disable the "injector flow values not programmed" codes, because Im not sure if the LBZ ECM/GPCM would properly learn LMM injector values... I doubt thats going to cause a huge issue??


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