LFX Engine Questions
 

Haven't been able to find this info and didn't want to clutter up any of the build threads.

When purchasing an LFX motor for an engine swap...

1) Does it matter if the donor engine is auto or manual if I plan on putting on a new clutch and flywheel? Any other differences between the two motors that would make it preferential to get a manual motor?

2) Are all model years of the Camaro LFX engine the same (2012-2015)?

Thanks in advance for any help!

Engines are the same but you'll need to do more modification to the engine harness from an auto to make it work for manual. V8R can do the harness modification for you if you're not sure what to do on that.

Yeap, what they said. Ours was an Auto and I made all the changes to the harness. The hardest part was snagging the correct bolts for the flywheel (I thought I had the right PN written down in my thread but they were incorrect).

Okay, thanks for all the info guys! The auto engines are just way easier to find, but I'll keep my eyes out for a manual and get the clutch, flywheel and harness with it.

Found this the other day and thought it was pretty cool. Complete assembly of a LFX on How It's Made.

My LFX motor was out of an automatic transmission car. If you go this route you will need a custom harness as well as an extra specifically out of a manual trans Camaro. Also will need a pack of the flywheel to crank bolts for a manual trans car as the ones from the flex plate won't fit.

Has anyone seen a build thread for an LFX swap in an NB, or one where ABS was retained?

The only NB LFX I've seen is the V8R MSM and it seems they pulled the ABS.

I work for a GMC/Buick dealership. PM me with any questions you may have. I have access to connector diagrams as well as many other things. I also pay 10 percent above cost on O.E. parts.

The LFX engine can be had from many other vehicles not just a Camaro. Acadia, Enclave, Lacrosse, Traverse, Terrain all have V6 options with displacement ranging from 3.0 to 3.6. The Camaro makes the easiest swap as it is already configured from RWD. If getting a FWD motor you'd need to swap the intake manifold and probably the TStat housing out. Harness isnt hard to modify, you'd need to swap some pins and get a manual trans ECU. I dont think an Auto Ecu can be reprogrammed for manual configuration but if you go standalone or use HP Tuners I think you'll be alright.

You rock, thanks for the info!

ABS is whole separate system, should not be an issue

I was thinking from a clearance point of view. The V8R MSM had a bunch of stuff right where the ABS module would have been.

Schmoo, you can always extend brake hard lines and ABS module wires to relocate the ABS module wherever you need. But I wouldn't make it stray too far from the MC. Hell if there was clearance in the cowl area or under the dash it would work. Only downside to having it inside the car would be pump noise whenever the ABS kicked on.

Definitely.
I'm considering this swap so I'm trying to understand as many of the implications as possible for my car, an MSM.

I thought the idea was to have the coolant reservoir at the highest point of the engine which makes your choice limited. It's going to either be on the back of engine bay on the right or left. I have mine on the right side where everybody put theirs just because the bottom of the reservoir goes to the coolant return line which happens to be on the right side as well. I suppose you could figure out a way to get it in the windshield wiper area. I have an auto ECU in my car, but haven't driven the car yet. It did start at least once upon a time.

Highest point aids in bleeding bubbles from the system, but the bottom of the reservoir doesn't need to be higher than the highest point in the system - just the cap.

I've been thinking about moving mine to the windshield wiper area, especially since I don't have wipers in the way. Probably need to make a custom reservoir to fit there though.

Starting my LFX swap and glad that you guys have done such a good job of sharing info like this.
thanks

From my experience a manual PCM is required. My first PCM was a E39 out of an Auto trans car and even after changing every possible parameter in HPtuners, it still wouldn't rev over 4,000. Its like it was still looking for data from an auto trans, even though the harness and settings were all selected as manual trans.

I don't have the PCM yet but knew about getting the correct one from reading the build threads. I don't stand a chance of tweeking one with HPtuners so will buy one complete and done from someone who knows what they are doing.

There's a rev limiter by gear table, I'll see if I can screenshot it.

I've see some other guys with a similar problem I think it has to do with the Park/Neutral into the ECU. If I remember correctly the rev limiter is set to 3600 whenever it detects a Park/Neutral signal. I'm running an auto ECU from a Camaro. I never tried actually revving it up that high when it was running (it still hasn't left the garage). My ECU seems to have died right now and I have no 5v reference signals, so I can't test that theory right now, but I thought it was something I stumbled across in one of the manuals. I'll see if I can dig that bit of info out.

https://cimg3.ibsrv.net/gimg/www.mia...1239920710.png

HP Tuners comparison function is pretty useful. But there's your limiter.

Great find! Thank you. This will help future builders

What did you use for a park/neutral signal? 12V? Did you ever try just disconnecting that signal?

ended up finding the correct manual ECU and thats all it needed.

I have been collecting parts for my swap and I am not the most techy guy so I bought a new wire harness, New GM ECU that has been re-flashed with a tune and deletes needed and came with the pigtail for the pedal and the OBDII from Andrew at Keisler Automation for under $1250. Its turn key and ready to go, such a smokin' deal since I would have struggled to figure it all out. When I start my build log I will post up the results.

Where did you get a manual ECU? The ebay guys are clueless.

Just spoke with V8 Roadsters today about the ECM. My donor is a 2015 auto camaro and they told me I need the GM ECM with the part number 12648906. If you search this on ebay you can get them for about $60 all day long.

Edit: ^^^ This info is wrong.

https://www.miataturbo.net/build-thr...x-build-95543/ Here's a short thread on my NB LFX build. I didn't show the whole process, since other guy's had done a good job with that.

Again, beware buying off ebay without knowing exactly what you need.

12648906 is the E39 part number - but you need to be 100% positive that you're getting one from a similar setup, as that part number also includes 4 cylinder non-LFX engines. You have a few more options since you're retaining auto.

Shitballs, are there any other identifiers to make sure it is the proper ECM?

I'm going MV7 manual and ditching the auto.

This is the one I bought today.
https://www.ebay.com/itm/282654934414

Cancel your order if you can. I'll see if I can find the post in my build thread where I talk about ECU options - https://www.miataturbo.net/build-thr...0/#post1390446 https://www.miataturbo.net/build-thr...1/#post1471054

Damnit, pretty sure they already shipped it. I found a 2013 camaro lfx 6-speed ecm at a Texas salvage yard for $40. Car-part.com lets you sort through the engine control boxes for specific years and models and you can also see if they are from a 6-speed car.

Thanks for the pm and heads up! I guess it is off to the gun range for the ebay ecm.

I'm going to Overkill for the E85 kit and tune, so as long as it is from a 6-speed camaro lfx it should be fine.

ECM selection is a real PITA - GM purposefully makes it not easy under the guise of 'security', and I had a bunch of learning to do before we got ours right. On my LS3 it was a bit easier, since you can bench flash the E38's, I paid a little bit extra and got a proper Camaro flash on mine. And even with car-part, I'd call the yard and make sure they're not substituting a part that follows a serv #. Car-part (on top of the search interface) offers that database as potential substitutions to the yards.

Thank you and GREAT advice! I'll confirm that it is actually from that car.

I thought there was a bit more to this. Getting a flashable ECU was only part of the issue if it is not from a v6 camaro six speed. The ECU has to be flashed with a different VIN number. GM assigns software paramaters based off the VIN. You can get it to run with Auto tune, but the ECU won't change the torque parameters, at least that's my understanding.

I wasn't able to flash my ECU with EFI Live and I can't remember why now. I may have just been out of credits.

If that was right then wouldn't there be no working LFX swaps? Not trying to be a smartass, just trying to understand this so I can get the right ecu.

They probably all have the same VIN. It's possible to reprogram, but you you're going to have to steal a VIN..You can easily do it by simply doing a search for a 15 camaro v6 six speed and stealing that VIN.. I don't know about how legal that is, but it's very easy. I'm just not sure how to Flash it. I paid a guy to flash mines, not sure if that is legal or not and I assume that's why people are staying pretty tight lipped out it. I don't know if you can do it with EFI Live or HP Tuners. I'm sure somebody else can chime in on what they did.

So I may have to expand upon this further (probably in my own thread) on HPTuners and GM ECM's as a whole.

But to try and shed a little light on this without going into heavy detail - 3 things to keep in mind:

MFG PN: This is the actual GM part number. There are multiple "E39" ECM's that share the same processor but slightly different hardware - different pinouts, options, etc.
SERV #: This is the compatible-matrix of read-only software on the device that can be changed between different models - IE, an Acadia with an inline-4 shares the same Serv # as the V6 Camaro - and can be turned into a Camaro ECM provided it is flashed with GM tools inside the target vehicle. I'm oversimplifying things here, but roll with it. If you put an Acadia ECM into the Camaro, all the other canbus devices in the Camaro have to agree that this new ECM can be flashed to the new Camaro software. Since most of us don't have a working Camaro hanging around, this eliminates the option of readily changing any old ECM into a Camaro. Older ECM's can do this much easier - it's called bench flashing - and you can take any old E38 Sierra ECM and turn it into a Corvette ECM on the bench without needing an entire working car to do so.
Software Version: Due to the nature of HP Tuners / EFI live, they cannot "install" new software onto the ECM - IE, they can't copy the manualtransmission.exe from another ECM and install it onto your ECM that's already set up as an automatic - that's software piracy. They can, however, edit some of the bits that are already there - like changing your fuel tables, and disabling the vehicle anti theft system. Older ECM's already had manualtransmission.exe and automatictransmission.exe on them, and the tuner programs could edit the bits to tell the main program which to use.

So - long story short - The easiest way to make sure everything works is to get the right ECU the first time. Buying a ECM off of rockauto / ebay / GM is possible - but those are sold with the expectation they'll be reflashed with the GM software inside a working vehicle. Bench flashing is not allowed with E39/E39a ECM's. Tuner software does not add any new software - it only changes what is already on there.

Another couple quick questions on LFX parts...

I saw a link to summit on here for a new LUK LFX clutch kit and now can't find it for the life of me. Anyone have a link?

Also, what are the correct GM part numbers for the flywheel bolts?

11588884 - 8x required - annoyingly, even the LuK kit came with the automatic bolts(!?!)
LuK kit 04-262 - https://www.summitracing.com/parts/luk-04-262

You rock! Thanks Brother.

Finally found a salvage yard on car-part.com that would confirm the ECM came from a 2015 camaro V6 w/ a 6-speed manual and were willing to ship it for $75 total. Amazing how many told me they wouldn't ship it out of state. Wtf?

Erm - crap, 2015 is gonna be an E39a ECM, and might have issues with the alternator control.

haha, I just can't win with this.

If it is a 2015 engine and 2015 alternator why would there be an issue?

Needs the BCM because of course we had to make the alternators too damn smart.

GM charging system problems ? Ricks Free Auto Repair Advice Ricks Free Auto Repair Advice | Automotive Repair Tips and How-To

The DR44 alternator (2 pin) has a field and a sense wire. The E39 with hptuners and alternator override will default to 13.8v output. E39a's wont enable the Field wire, which won't produce voltage. I'm working on a simple 555 timer circuit that'll produce the right 128hz PWM signal, but I just got around to designing it last week.

Got it. Okay, please treat me like a 5 year old for this so I don't fuck it up again.

Is there a specific year 6-speed camaro 3.6 lfx ECM that is guaranteed to work?

And do I need a different alternator than the 2015 model that comes with my engine?

Serv #: 12643248 - should cover 2012 Camaro, has PN of 12648906 (E39), with a VIN of 1G1FE, 1G1FF, or 1G1FG (indicating manual transmission). Annoyingly https://service.gm.com/dealerworld/v...013%20r1.7.pdf doesn't appear to be loading. edit: https://www.camaro5.com/forums/showthread.php?t=266853 has the decoder.

Alternator should work, it's just the control is different.

Yeah getting the salvage yards to give me a vin from the donor and confirm the details and ship is going to be a mess. I see why this is such a nightmare now.

Thanks for the help Brother!

So far the salvage yards think I'm a moron and are telling me I have no idea what I'm talking about. This is gonna be fun. :bang:

Score!!!!

Okay, so a bit of advice for anyone trying to track down an ECM for a LFX swap...

Go on car-part.com and search for a 2012 camaro 3.6 engine. Look for an engine that shows it as being a 6-speed manual car. Hopefully they show pics of the car in the images and you can confirm the vin. Call and get the ECM.

Totally lucked out and found one 20 minutes away in Austin. Just went and picked it up on my lunch break. I saw the car and it was indeed a 6-speed. The vin pic I took at the actual car. Btw, if anyone needs a vin for any reason on their ecm, feel free to use this one.

Please tell me this is the right one...


https://cimg5.ibsrv.net/gimg/www.mia...98eac2c448.jpg
https://cimg7.ibsrv.net/gimg/www.mia...9a91f4677b.jpg

Hurray!

Besides the Miatas I have a C5 Vette, and I gotta say, GM and their electronics...what a huge PITA they are.

Anyone know what size bolts to use to get the LFX on an engine stand?

Edit: Found it in DJWade's build thread... "M10x1.5 x 75mm is what you want if you're using a harbor freight/torin engine stand, or at least the 'T' leg version"

Running into an issue trying to find the trans housing to engine bolts.

Portabull listed the part # as 11515770 in his build thread. That is the same part # I'm seeing here:
https://chevrolet.7zap.com/en/camaro...7923382-0-0/#4

When I go to order them though, they show as alternator bolts on every website and nowhere else do they show as transmission bolts.
https://www.gmpartsdirect.com/oem-pa...-bolt-11515770

Can anyone confirm if those are the correct bolts?

Looks right to me. And a tip - the pennies you save buying from gmpartsdirect or similar is lost when you need to return them - I never heard anything good about them. I made friends with the local Chevy parts counter guy (well, annoyed him lots) but he always returned the parts that don't fit with too much fuss - though waiting a day or five to come from the warehouse (depending on the warehouse). And GM's complete parts listing isn't online - parts counter guy has a better resource that - but to speed things up, have a 5spd camaro VIN handy. I would usually find as many part numbers as I could, then rattle them off to him and verify they were more or less correct on his screen as to the application.

Yeah, I'm finding parts lookup online to be a bit of a pain in the ass. Many of the parts I'm trying to look up either don't have an image or are buried in one of 20 different parts diagrams that only show a tiny drawing of the part. Then I google it to see if I can find a picture on ebay or somewhere else.

Thanks!

Found a gem... Chevrolet Equinox Service Manual - Engine - Powertrain

It's for the equinox, not the camaro, but this site has the full service manual for the LFX on it. I was struggling to find some torque specs and replacement procedures for a few parts and this had it all.