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Used LF3 Could Be The Perfect Crate Motor For Your Transverse-Engined Project Car

We can hardly wait to get our hands on the incoming Cadillac CT6 sedan, which seems set to replace the slow selling, front-wheel-drive-based XTS. While it’s tough to make a case to keep the soon-to-be-irrelevant Epsilon II-based sedan, we are sure to miss its available twin-turbo 3.6L LF3 V6 in the XTS Vsport model, which is good for a heady 410 hp and 369 lb-ft of torque.

Thankfully, the folks at Preownedengines.com have realized its potential and now you can buy your own used LF3 engine through them, without having to break the bank on a used XTS. (Yes, you can still find the LF3 in the Cadillac CTS Vsport in longitudinal form, but that’ll cost you even more.)

Introduced in 2013, the transverse 60-degree six-cylinder can easily fit into any Epsilon II-based vehicle, like a ninth or tenth-gen Chevrolet Impala or Buick LaCrosse, and you can likely shoehorn it into many other transverse vehicle applications with a bit more wrenching and wiggling.

The lightweight block, made from aluminum, offers significant weight advantages over a cast-iron block and you can fully expect between 17 and 27 mpg, according to the retailer.

The company also says that the engine has been tested with the 6T70 and 6T75 automatic transmissions, which means you could theoretically turn a Pontiac G6 GTP (the only G6 with the 6T70) into a 410 hp, white-knuckle monster.

The engine applications are nearly endless– all you need is the LF3.

A far-too-tall Ontarian who likes to focus on the business end of the auto industry, in part because he's too tall to safely swap cogs in a Corvette Stingray.

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Comments

  1. That’d be fun in the current gen Malibu lol

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  2. I wonder if it would fit in a Buick Regal GS ?

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  3. While you could make some neat cars the cost alone would run more than the project would be worth.

    You really would have to do it for the love.

    Not sure if you would ever get the FWD balance and stability in some of the others cars with this much power. It really needs engineered in.

    I would much rather fit an engine like this to a RWD car like an older 78 Malibu or a rwd Fiero if you could work out the issues of heat in the back as well as where to put the intercoolers.

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    1. this motor is in the ATS-V and it is a RWD car

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      1. Transverse version was available in the XTS-V…

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      2. So I have a 2015 Malibu 2.0t. How difficult would it be to swap the lf3 into it. Also would it fit with the trans I have in it?

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  4. The problem with the LF3 is the ECU. How do you get this, to talk to any modern GM car?

    I’m not even sure the ECU will talk to a Malibu or a Lucerne. Ever since Global A, all that is encrypted to hell.

    GM would do the performance community a huge favor if it just open-sourced its ECU. All the auto makers reverse engineer all the telemetry data that could possibly be stored in it.

    The first auto maker that does this, will be the darling of the performance world.

    Until then, I wouldn’t touch this with a 410 foot pole.

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    1. While this has been brought up on nearly every generation of vehicle nearly all have been figured out or things have been offered to help adapt.

      People like Painless Wireing have made harnesses and adaptors. Also other tuners have offered services to tune the computers to the engine.

      GM generally uses the same computer with only a different flash per each car. Tuning of late and making things work has really been easier than ever to adapt but with so many things controlled it does take a little more work. Even things like the radio are now tied to the computer.

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    2. I would think it would do on the Malibu or Lacrosse as both are on the same platform

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    3. What about using a “used ECU” from one of the vehicles it was available in?

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      1. The problem is the programming. A used ECU is tuned and dyno’ed at the factory to the donor car. You need to program and tune it.

        The 2000’s were actually worse, as the ECU and TCM were consolidated into one device. So you couldn’t have a separate transmission that was different from the matching engine.

        But you still need a tuner – someone who has reverse engineered the engine. Trifecta and HPTuners are getting better at adjusting to newer GM engines, but it’s still not where it should be. I realize there’s a lot of secret sauce, but there should at least be a licensing program.

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        1. if you grab the speedo key fob security (patf) module, tcm, and ecu from a donor car you are in bizznizz

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          1. I sincerely hope you read my post. Having a TCM in your hand, and getting a GM LF3-mated TCM to talk to your car, its transmission, and its systems, let alone the ECU and tuning that is non-trivial.

            Yes, GM did a good thing by separating the ECM and TCM in Global A cars, but without TCM documentation – it’s still an uphill battle for any project car. This is the stuff that should be open-sourced, it helps nobody (patents still work to protect innovation between auto makers) – and would prevent things like Dieselgate, since we would all see the calibrations in real time.

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    4. Because it would not communicate with chevy’s base software? Correct??

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  5. What a great way to revive a HT4100 Allante’

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    1. Now that would be interesting if it would not torque steer you into the ditch.

      I know my FWD at 300 HP has most torque steer tuned out but it still can take a stab at you once in a while if one of the tires get loose from the other.

      I would really love to see this in the Allante.

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  6. I wonder how much hell this thing would be to “gently massage” into a 91 lumina… It would make a great sleeper car, for sure.

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  7. I want it for a 2015 Camaro to use front wheel drive and then use 2 – 272 hp electric motors, one for each rear wheel as a drag car. I would have app ~ 954 hp but only be showing the 410 for the front wheel drive V6, now that’s a sleeper car. Plus dry nitrous to compensate for the turbo lag.

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  8. Wonder if you could fit one these in a Saturn Skye?

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    1. youtube search saturn sky v8. if a lsa can fit this surely can

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  9. How about a 2009 Pontiac G8? It currently possesses the 3.6L LY7, I’ve thought of swapping it for the LF3 but that would be pricey, and the tranny would most likely have to be swapped as well. My conclusion, find a used LF3 and grab the whole turbo system for my engine, assuming the headers mount to the LY7…..if not, I think it could still be persuaded.

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  10. Am I the only one that think this would be killer in a corvair, rear engine rwd with 400hp and independent suspension. Can you say porche killer, and you more than likely just run a simple standalone since the corvair is old and doesn’t have the complex electronics.

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    1. I would love to see that corvair.

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  11. adapt a standalone aftermkt ECU…???
    Use std injectors instead of sidi?
    should be ways to build this. I have a 2013 3.6
    camaro thinking of installing into 94 toyota 4×4….w/o 4×4…..rwd all the way….
    Challenging…not impossible. Nice motor

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  12. i have a 2013 cts im just wondering if that would be a direct swap out

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  13. I have a fabrication shop. 🙂

    I’d bet this would be good motor for a rat rod or an older VW kit car body with a custom chassis.

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  14. I want to get one of these for my ’17 Impala. I was wondering if the computer would match up easily, and would I have to beef up the transmission??

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    1. Honestly unless your engine failed, you will save more money by just trading for an XTS Vsport.

      Now if it did fail, you could try contacting Trifecta. They would know the calibration aspect. You definitely would have to amp up brakes and suspension.

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  15. I have a 07 Pontiac GTP. 3.6. 252 hp with 6 speed . Sedan roughly 3,200 pounds the lightest of all g6 models. I would definitely be willing to do a crate motor swap for the lf3 . 150 horsepower upgrade and 100 lb of torque. Probably talking 0 to 60 in Low. 3 second

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  16. Hi Christopher, I have a 2012 CTS 3.6 AWD, could I swap in the 3.6 LF4 engine?

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    1. The big problem is computers. The ECM and TCM for that engine are separate and totally different.

      Just in general, Sigma I and Sigma II cars share engines with Zeta, Corvettes, GTO, and other LS1/LS2-based powerplants. Newer cars share electrical components with the LT1

      You’re better off putting an LS7 or an LS9 in. All the ECM’s and tunings are readily available and it will go much more smoothly.

      On the plus side, the 2012 CTS is really the last “moddable” vintage. All the newer Global A Caddys are so locked down, replacing the powerplants is going to be a mess for people doing it.

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  17. ok what if i also swap in the ECM & wiring harness with the LF4 engine (and anything else i need) will it sit on my current motor mounts and mate to that 2012 AWD transmission?

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    1. The problem is the transmission and TCM on the 2012 CTS are meant to be part of the same ECU as the engine.

      GM split them up with the LF4, which was meant to make it easier to mod those cars – since they made everything else ridiculously hard on them.

      But in terms of backporting, the problem is when you take that LS2-era motor out, the transmission loses its TCM.

      And that’s before you get to the AWD configuration handling vastly different torque and horsepower. GM didn’t ever ship AWD system over 310/320 horsepower in production. It was a really old AWD system that dated back to the 1990’s. It worked fine, but couldn’t handle high outputs.

      I don’t know how it would handle 400+ horsepower.

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  18. do you think it would be ok to supercharge the LFX engine http://www.getoverkilled.ca makes a kit that will boost between 8 – 9 psi and a stage 2 kit between 10 – 12 psi .. they claim engine and trans with accept the extra boost.

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    1. I think you’re risking the AWD system for anything over 320 horsepower. It was a huge limiting factor for that platform. They really considered putting a V8 in the sub-V CTS, but the STS (which shared the same AWD system on the older platform) even with the standard Northstar V8 topped out at 320 horsepower.

      Somewhere between 320 and 450 horsepower, the AWD system gives out. We don’t know where.

      For a RWD car it is much more straightforward.

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  19. I’m planning a project using a 3.6 liter twin-turbo V6 LF3 in a 2012-2015 GMC Terrain.
    I have really enjoyed the 3.6 V6 in my 2015 AWD Terrain but there is limited aftermarket availability.
    Looking into options to stay in the GM 3.6 V6 I have found the 3.6 liter twin-turbo V6 LF3 that is in some other GM made products.
    With all that being said, what challenges will I be facing to do this swap?
    Also I’m considering a sequential shifter or paddle shifter in this build.
    Any and all thoughts would be appreciated, I’m dead set on making a Terrain build like no other since GM doesn’t make any performance versions of it.

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  20. Has anyone swapped out the 307 from an old school caddy with a 3.6 from a newer Camaro? Just curious because I have the chance to buy a totaled (rear impact) 2014 V6 Camaro with 67k miles from a friend for $1500 and was planning to use the engine/transmission in my 89 Brougham. Would rather have a V8 but 330hp V6 doesn’t sound too bad for the money.

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  21. Would the engine fit into a 2008 Saturn Outlook XR?

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  22. I have a 2013 CTS4 coupe with the 3.6 v6 engine. I was wondering if I can get the LF3 or LF4 twin turbo engine to fit in my 2013.

    If anyone knows would be appreciated to know more.

    Reply

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