What do we like for LS-swap ECUs?

I'm doing the preliminary planning for my LS swap, and am curious about opinions on controlling it and the transmission.  Right now, the plan is for a 3rd gen engine, hopefully a 6.0 LQ4, cable throttle, and a 4L80E transmission.  Will need to be able to handle boost.  Seems like using a GM ECU, and having it tuned may be the easy button, so that is my first choice, but I am curious to hear other opinions?  Seems like Holley has gotten into the game, and is reasonably priced, but adding a transmission controller kicks the price way up.  Megasquirt is an option, but I hear a lot of dyno shops don't like messing with it.  I looked at Haltech, but about choked on the price.

Stock ECU is not only easy button, but best button.  Tuning requirements will be minimal and it's far more robust and sophisticated than aftermarket computers.  Engineers slaved over all sorts of obscure tables to get the tune right, and it's those obscure idle, intake manifold wall wetting modeling, temperature compesation and modeling, etc. maps that are the part of aftermarket computers that are so hard to get right that most people just ignore them and live with an engine that occasionally runs like crap.

You'll be wanting a '99 up computer if you want to control a 4L80 and you'll also need to make sure it has the IAC control circuitry.  This generally means "6.0 van".

Yeah, no personal experience but everyone I know who messes with LSes says to stick with stock ECUs unless you're doing something radical.  I'm told there are two different LS ECUs based on how many teeth are in the crank trigger wheel, so make sure you get the right one.

In reply to codrus (Forum Supporter) :

Aside from some GTOs, that's fairly easy.  All drive by cable capable computers work with the 24x crank, so that is what you need engine-wise.

Also, shortly after the switch to 58x, they went to separate ECMs and TCMs instead of a single PCM.  One advantage of these is that they got rid of the TAC module, using the ECM to directly read accelerator inputs and control the throttle body.... but this is irrelevant if one would prefer a cable throttle.

Street car: Stock ecu, especially for 4L80e control.  Dedicated drag car is when I would start thinking about a standalone.  I went with a Terminator X Max in my truck because I was afraid of wiring.  If I were to do it again I'd use a factory ECU.

Agree with pete.  I love stock ecu + hptuners.  I hear there's some sort of free ls tuner now?  

Interestingly, I am in the exact same boat.

In my '61 Chevy pickup I have an '07 LQ4/4L80E drive-by-wire pulled from a van, to which I've added a 7875 turbo.

Since I'm still intending to run a stock cam, keeping the stock tune (just scaling it to fit a 2 or 3-bar VE table) makes sure I maintain all the perfection that GM provided as far as economy, cold start, driveability, etc.

HPTuners  will set me back $525CDN for the kit and credits.  Add to that a wideband for $300 more, and I'm in for $825CDN.  Add an electronic boost controller and Meth injection and it starts adding up.

The Terminator X Max setup in DBW and trans control will set me back $2000cdn.  BUT, it comes with a wideband, can serve as a boost controller (which would be $600cdn), meth controller ($400cdn), and traction controller (???).

It starts adding to be almost on par, but as mentioned above, it's going to depend on how serious you want to get.

While I built the engine for 22psi boost, I imagine I will be too scared to even approach that, much less need meth injection, on a street-driven 60-year-old 2wd pickup.

If you just want fun, HPT.  If you see yourself going down the rabbit hole, Terminator X Max.

(Terminator can't do cruise control.....)

The free tuner is TunerPro and LS Droid.  I've used TunerPro, but not LS Droid.

Pete. (l33t FS) said:

Stock ECU is not only easy button, but best button.  Tuning requirements will be minimal and it's far more robust and sophisticated than aftermarket computers.  Engineers slaved over all sorts of obscure tables to get the tune right, and it's those obscure idle, intake manifold wall wetting modeling, temperature compesation and modeling, etc. maps that are the part of aftermarket computers that are so hard to get right that most people just ignore them and live with an engine that occasionally runs like crap.

 

You'll be wanting a '99 up computer if you want to control a 4L80 and you'll also need to make sure it has the IAC control circuitry.  This generally means "6.0 van".

All of this.  You won't necessarily be hooking it up to a USB and your laptop, but the level of control you have with a stock ECM is not something you'll find in aftermarket stuff.

I used to have pages bookmarked but can't find them.  There are sites that list ECMs that do and don't have the IAC controller.  IIRC, the vans are a usual go-to.  They almost all have the drivers for IAC and flex fuel.  The drive-by-wire vehicles often don't have the IAC driver because the throttle is the IAC.

Lt1swap.com

SkinnyG (Forum Supporter) said:

The free tuner is TunerPro and LS Droid.  I've used TunerPro, but not LS Droid.

And how was it??

May need to do a little tweaking but didnt want to shell for HpTuners.....

My '07 Express ECU came DBW, but apparently has the hardware in it to run IAC.  ECU 12602801.

TunerPro in my case (old GM TBI) used a .bin file (your tune), an .xdf file (the "mask" to interpret hexidecimal into English), an .adx file (what you are going to datalog), and ultimately you create an .xdl file of the datalog.

The software itself was a bit confusing at first, but you eventually figure it out as you poke around.  If the dude who created the "mask" was kind, there should be lots of notes to help you know what to do or change.  In my case, I was using a antiquated ECU that nobody had developed further, so I spent more time figuring things out and adding more notes.

If you can do Megasquirt, this isn't that far off.

I have no experience with TunerPro other than this, but I figured it out, and since forgotten most of it (sold the car in '19).

If I can't find a "mask" for my ECU, or if I cannot change the bins for 3-bar, I will likely shell out for HPT.  I am a long ways off from having to worry about it yet.

There is likely other tuning software out there as well.

Let's just say that hypothetically speaking, you disabled the front 4 cylinders, could the stock ECU be programmed to ignore them and run just the rear 4 cylinders?...Or is that a go directly to stand alone, do not pass GO, do not collect $200 situation?

Driven5 said:

Let's just say that hypothetically speaking, you disabled the front 4 cylinders, could the stock ECU be programmed to ignore them and run just the rear 4 cylinders?...Or is that a go directly to stand alone, do not pass GO, do not collect $200 situation?

I don't see why not.  You wouldn't disable the cylinders in software, but you would have to disable codes relating to ignition coil and fuel injector circuits, and you'd probably have to eliminate misfire detection too.  If you used MAP-only then it'd probably work just fine, if you used a MAF sensor you might need to multiply the MAF transfer table  by two so the cylinder airmass math all works right.  The computer would just be assuming that the other four cylinders are there.

I've thought about this a bit, because I'd like to run just the right bank of a 5.3 in the RX-7.

In reply to Pete. (l33t FS) :

Well that's good to hear. Thanks!

So, where does one go for further information on late model obd2 and tunerpro/ls droid? Before I spend the money on hp tuners....

Dusterbd13-michael (Forum Supporter) said:

So, where does one go for further information on late model obd2 and tunerpro/ls droid? Before I spend the money on hp tuners....

Facebook has a group but I warn you it's not for beginners. If you don't have a degree in coding and programing they will insult you like you've never been insulted before. 

I believe there is a YouTube video that will teach you how to remove the Vehicle Antitheft System (VATS). Tuning that software isn't for first timers or so I've been told. 

Update just because I stumbled onto this thread searching for something LS ECU-Tuning related....

I have my '61 Chevy running and driving with the LQ4/4L80E/7875, all mooching off the (adjusted) factory tune with HPTuners.

The more I've dabbled with HPTuners, the more I'm getting used to it.  LOTS of options, and with a lot of online resources, relatively straight forward to tune.

Things I didn't like:

• My drive-by-wire P59 ecu doesn't have the architecture to run 3-bar MAP.  Boo hoo, I know, but I guess had my hopes up too high.  Like I would even be able to put 22pis to the ground in a 2wd 60's half-ton with 245 tires....
• The spark table is in grams/second instead of kPa.  This has taken me some time to wrap my head around, but I setup a histogram in the VCM Scanner that shows me what g/s I'm at with respect to MAP and RPM.  I'm still wrapping my head around it.
• It take a lot of online digging to figure out what is going on and how to correct it, but that was a MegaSquirt thing for me years ago too.  Likely just familiarity.

Things I like:

• It pretty much fired up right away, even after having changed to a 2-BAR Operating system, and increasing the Injector Flow data to the decapped injectors I'm running. I did tweak the IFR numbers until I had zero VE correction, and the driving around town table is dang near spot-on right from the get-go.  Stock cam, mind you.
• It comes with traction control from the factory (really, it just calculates how much power you're making, and pulls timing to stay under what it thinks should be your "safe" level of power. (I zeroed that table for giggles)
• It has a safety table in the Drive-By-Wire system that if the engine is ingesting more air than it thinks it should be, so it'll go into "limp mode" so your car doesn't go all Toyota on you.  (I increased that table)
• There are lots of safeties with respect to temperature and such that pull timing, making it a pretty safe way of running your engine.  Unless you find all those tables and disable them.... I'm erring on the side of "safe" for now.

In reply to SkinnyG (Forum Supporter) :

You can get a bigger fuel map by doubling and dividing it. I forget which but that's how it's done. It's not a perfect solution but for what it's attempting to do it works fine.

I would have megasquirted on a fresh build. JMO. Fresh wiring vs reworking or having to use a new Chinese harness.

I don't think you can "make" a 3-bar system like that.  Some folks will just max the last row in the VE and spark tables and hope for the best.

I halved my injector flow rate, halved my VE table, and halved (almost) every table that referenced airflow (g/s) which allows my to not max the spark table at really low boost.  This is just a way to overcome the hard limitations in the code.  It does not change the fuel map.

Switching to a 2-Bar OS just changes 20 rows for 15-105kpa to now be 20 rows for 30-205kpa.

I was not maxing the code limits for injector flow. There are similar tricks for that, which includes halving the displacement of the motor and halving the injector flow.

I got a complete LQ4/4L80/pcm/wiring for $1000CDN ($700US), so that's the way I went. If I had to add Megasquirt, Megashift, and convert to cable throttle, I would not be further ahead than just buying HPT.

CARBUEROTROR

GOBLESS HOSS

Really the only reason I'd jump off of stock ECM on these is when I want all the fancy features (wideband, boost control, speed based traction control, sd card based logging, etc) included in a one box integrated solution. Even Holley and FT and adding all the boxes it's not a short put to get everything you want working, so you better have a great reason to.