LC9 with a manual trans - Seeking Advice

[green_weenie]

Hello everyone,

I think I have myself backed into a corner and need to spend some money to get myself out. I'd like some feedback from you all on what the best way to do that is without spending a pile of cash.

For background: I bought HP Tuners because me and a couple of my buddies are doing LS swaps and transmissions swaps in ECM-controlled vehicles, and I figured this would be a good way to get my feet wet and learn a new cool skill that I'd spend the same amount of money paying someone else to do. I am pretty mechanically savvy with older vehicles and I have a degree/job in engineering, so I'm hoping the concepts there are a good foundation to learn tuning.

Anyway, I've decided to cut my teeth on an LS swap for my 1978 K10 pickup. I'm going to run it stock for now just to see if I can get it to start, then maybe find some room in he budget for upgrades once I know where it's lacking. Long story short, I found what I thought was a good deal on a low-mileage LC9 out of a 2011 Silverado. Got it home before I realized that the Gen IVs are not the best engine for LS engine-only swaps. Whatever, lessons learned, I'll figure out how to make it work. Next I realized I was missing an ECM. No problem, I bought an E38 ECM out of a 2011 5.3 Silverado from a salvage yard on eBay. The way I figure, it's the ECM that goes with my engine. My next mistake: I bought/spent 2 credits to disable VATS/starter checks on the ECM (didn't get the engine to bench start but that's a different issue for another day...)

My trouble now is that I'm keeping the original 4 speed manual, and from the looks of it people are having mixed experiences mating a Gen IV to a manual with the original ECM OS. I've searched the forums trying to figure out my next move, and it looks like other people are experiencing the same thing but there's no solution posted (here and here)

In other places it's pretty clear that you have to do an OS rewrite or just buy an E38 set up for M/T (here and here and here and maybe here). It seems like this has something to do with the ECM requiring a VSS signal to run properly, which is transmitted in serial (GMLAN) via the TCM in automatics and direct to ECM in manuals. Is that correct?

In other places it looks like some guys got it to work alright (namely here). Definitely an "It works, but..." type of situation but nevertheless, it runs.


I guess the way I see it I have a few possible paths, and I'd like to figure out which one is most cost-effective that will let me run this engine well:

1: Fuss with tuning the ECM as is without a TCM and get it to work. Is this a fool's errand? Does my ECM need a TCM connected to even run at all? Has anyone personally done this successfully on this forum? What issues will I run up against? Definitely the cheapest option right now, if its feasible.
2: Get the OS reflashed for a manual setup and keep the current VIN/vehicle information intact so that I don't have to buy 2 more credits. Is this even possible? Where would I go to find someone able to do this?
3: Get the OS reflashed for a manual setup and buy 2 more credits so I can write over it. Will this get me what I need to be able to run the vehicle?
4: Buy an E38 ECM with a manual trans OS on eBay. I'll have to buy another 2 credits for this as well. Probably the most expensive option, but if it's necessary I can do that. If so, is there a particular ECM I should seek/avoid for compatibility's sake with my current engine?
...Is there another option I'm not seeing right now?

I'm just looking for information and advice, I see there's a lot of knowledge on this forum and the best way to learn is from others' experience and getting your own hands dirty. Thanks in advance!

[325_53]

I put that exact engine (LC9) mated to a TR6060 from a Camaro into an E46 BMW.

I purchased a cheap module for performing dealer level programming (VCX Nano - GM) which works great through GM's TDS website.
It took a bit of fiddling around, but essentially you can pay ~$50 per VIN for access to program any module in that vehicle via GM's SPS site using this tool. The VCX nano is a pain to setup.

What I ended up doing was searching e-bay/automotive adds/salvage auction sites only for a model vehicle VIN which matched my ECM requirements (Be aware of service OS years, yours being a 2011 should be fine with any 2010+ OS's) and use that VIN number to use GM's SPS to "replace" the module in that vehicle using your newly found VIN. GM's software will pick-up the correct OS for that vehicle and program your ECM to a factory version of that. Your best candidate would likely be a 2010+ Camaro - 6 speed, and then reference your original ECM's stock file and copy over all the timing/fuel/injector data/MAF/MAP/IAT data to match your LC9 parameters.

This will allow you have VSS via analog signal vs. Can-bus data used on the auto's.
Downside is you'll burn another 2 credits licensing this new ECM once you flash your existing one as a new OS/VIN.

Really depends if it's cheaper to send it away to be re-programmed, or if you plan on doing more of this, buying the tools may be the way to go for you.

Car has been running "standalone" in this configuration for 2+ years now without issue, only downsides to the E38 i've found so far is Cruise Control and AC request Signals are Can-Bus and i'm still trying to sort that out with BCM's and all that.

[blindsquirrel]

If you only need to program one or a few ECMs it's easier/cheaper to just buy them used and pre-programmed to a VIN you supply.

First, find a file in the repository with the stuff you need. Take the VIN from that file, go look up what Service Number it calls for (2010-up is all the same service number, used all the way through 2017 or something; everything before that is 1 or 2 years only, thus more rare, thus more $$$). Order the used correct-service-number ECM, give seller the VIN you want. If the service number is compatible, it doesn't matter if the seller has listed the ECM for a specific model or not, it can be programmed to be whatever your VIN is. (a 'Malibu 12633238' is almost guaranteed to be cheaper than a 'Corvette 12633238' - even though they are the exact same hardware)

Be aware that the existing truck pedal/TB are not likely to be compatible with a Corvette or any other car ECM OS.