LS ECU questions

Joe_U4

Joe_U4

Well-Known Member
Joined
Feb 3, 2022
Location
Raleigh
Let me start by saying I'm a Ford guy so everything LS is new to me. I have a new to me buggy with a LQ9 6.0 that is using an OEM ECM and stand-alone harness. It's a mild build, stock bottom end, BTR cam, F body intake, drive by wire, & MAF. Not a fan of DBW and I know the is an issue with the MAF (MAF voltage too high code). Already swapped out the MAF and it's not the issue so it's the harness or ECU. I also prefer speed density over MAF strategies. I understand the reliabilities of the OEM ECU and they seem like a popular choice for LS swaps. I need to be able to tune and make adjustments myself. It has a TH400 trans so no TCM needed.
So that brings up the following options:

1) OEM ECU with HP Tuners

2) Holley Terminator

3) FiTech (I see mixed reviews)

What say you and your experiences?
 
A lot of guys refuse to tune with stock and hp tuners now. I’m assuming the epa has cracked down as they magically changed the hp tuner as well. Holley is nice and also can a lot easier provide a dash. But the harness it’s self is shittier than a eBay swap 100$ harness. Like a 2 year old loomed and taped it. I reworked a lot of mine. But I’d imagine just a can and speed density wouldn’t be much trouble to keep what you got. I run fitech in my jeep but it’s the carb conversion one. Never an issue and have done several cars with it. But not the Ls kit.
 
Just remember you need to add a separate intake air temperature sensor when you go SD so it doesn't freak out and do weird stuff with the timing tables.

Speed density will work just fine, I've just never seen it as a necessity unless you're running enough boost that it's above what the MAF can read and you get in to theoretical tuning.

FWIW, I like stock and HP Tuners. It's reliable and a bunch of folks know how to use it, but the ease of changing things and the whole dash display is pretty sweet with the other stuff.
 
Croatan_Kid said:
Just remember you need to add a separate intake air temperature sensor when you go SD so it doesn't freak out and do weird stuff with the timing tables.

Speed density will work just fine, I've just never seen it as a necessity unless you're running enough boost that it's above what the MAF can read and you get in to theoretical tuning.
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MAF is a pain to integrate in a short intake track and airflow reverb will absolutely ruin your life depending on the way the air flows in said intake track.
It's also more prone to getting wet and other fun stuff you encounter offroading.

Croatan_Kid said:
FWIW, I like stock and HP Tuners. It's reliable and a bunch of folks know how to use it, but the ease of changing things and the whole dash display is pretty sweet with the other stuff.
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You can also get a dash display with a more modern OEM ECU, just need to look into the Gen4 stuff. E38 or E67 will be supported by AEM, AIM, Haltech or other OBD2 dashes.
 
Don't need a digital display, I've already have analog gauges. I like the reliability of the stock ECU and leaning towards HP Tuners as it's the most cost-effective route.

I should only need one credit since I don't have a TCM correct?
I assume I can simply turn off DBW and change the TB?
I have read that the DBW does not have IAC?
 
Joe_U4 said:
Don't need a digital display, I've already have analog gauges. I like the reliability of the stock ECU and leaning towards HP Tuners as it's the most cost-effective route.

I should only need one credit since I don't have a TCM correct?
I assume I can simply turn off DBW and change the TB?
I have read that the DBW does not have IAC?
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I believe it’s 2 different ecu and harnesses.
 
Terminator is dead simple and only power and grounds need run. It also eliminates vat codes etc and the mass air flow sensor so it makes intake routing easier. You just need to get the right version std max etc based on whether it’s a cable or throttle by wire, what gen ls (2 diff crank sensors between 3rd and 4th) and what trans you’re running, auto vs manual.

Plus it’s 100% new wires and plugs and not some repinned 20 year old plastic plugs and an aging ecu
 
Joe_U4 said:
Don't need a digital display, I've already have analog gauges. I like the reliability of the stock ECU and leaning towards HP Tuners as it's the most cost-effective route.

I should only need one credit since I don't have a TCM correct?
I assume I can simply turn off DBW and change the TB?
I have read that the DBW does not have IAC?
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2 credits
Yes but no. You need to know how to parameter this properly. There isn't a "switch" in the tune.
Correct, IAC control is done directly with the throttle blade. That also means that not all DBW ECUs are able to control a DBC IAC, some are lacking the chip to do so.
 
I can't remember if 1 bar SD requires more credits or not. I don't think it does...it's essentially SD below 4000 RPM already anyway. Best I can remember, you disable/fail the MAF, add a separate IAT sensor (should be tan and black wires in the MAF plug that go to IAT), change low octane spark tables to the same as high octane spark tables, and then work on dialing in the VE tables with a wideband.

I know 2 and 3 bar require two more credits because they require a custom OS.

As said above, it's a bit more work to swap DBW to DBC or vice versa. I'm not a massive fan of DBW myself. If it's not giving you a lot of trouble, I'd probably roll with it, unless you just absolutely want a DBC setup.
 
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After debating this issue and researching I think I'm going with a Holley Terminator.

Simple, clean install, and the Terminator works with AEM displays. I already have a two displays, a CD-5 & 7.

SwitchPro 8 to control everything else.
 
Holley bought AEM so they should have updated firmware to talk to a CD-7. Haven't decided whether to use it or not. Already have full analog gauges so it's overkill and might be tacky.

Ordered a Terminator X 550-903 and it arrived yesterday. Also ordered fuel & oil pressure sensors.

Need to order a DBW TB, cable, & pedal now. Anyone have recommendations on a cheap TB?

Adding a oil cooler and I assume the OEM return port is the best place to plumb an Accumulator?
 
Bebop said:
If you say so
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Holley nor AEM knows shit. Holley says call AEM. AEM says it doesn't work with the Terminator X or Max, only the Dominator. Apparently the Terminator and Donimator uses different CAN protocols. Yet I have found examples of it working on the Holley forums 🤣
 
Joe_U4 said:
Holley nor AEM knows shit. Holley says call AEM. AEM says it doesn't work with the Terminator X or Max, only the Dominator. Apparently the Terminator and Donimator uses different CAN protocols. Yet I have found examples of it working on the Holley forums 🤣
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Joe, if that helps you trust my word, know that I wire cars and configure Can Bus protocols as a money making endeavor. With pretty good success too I may add.
If you want an AEM CD dash (5 or 7 doesn't matter) to play nice with a Holley ECU, you need a HP, a Dominator or a TerminatorX Max.
The TerminatorX (not MAX) doesn't have the ability to send the Racepak Can protocol needed to connect with the AEM dash on the only CanBus line available.
 
I appreciate the insight and you are correct. I opened up the X and there is only one CAN bus. I had read that the lastest models were shipping with two buses, wrong 🤷

Just figured I might use a AEM display since I had one laying on the self but not a big deal. It's doable with a custom CAN harness and packet sniffer but that requires more time and effort than I willing to put into it. The "juice is not worth the squeeze". 🤣
 
Joe_U4 said:
Adding a oil cooler and I assume the OEM return port is the best place to plumb an Accumulator?
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Mine is plumbed into the oil galley plug at the front of the block on the driver’s side.

IMG_1333.jpeg
 
DSM Turbos said:
Return it all and go fuel tech!
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where is the puke emoji when you need one
And before you scream, please explain why you are saying this. Do you have first hand experience with Fueltech? What is better than a Holley/ AEM CD dash with that other option?

Joe_U4 said:
I appreciate the insight and you are correct. I opened up the X and there is only one CAN bus. I had read that the lastest models were shipping with two buses, wrong 🤷

Just figured I might use a AEM display since I had one laying on the self but not a big deal. It's doable with a custom CAN harness and packet sniffer but that requires more time and effort than I willing to put into it. The "juice is not worth the squeeze". 🤣
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Anything is possible.
What custom Can harness?
 
Bebop said:
What custom Can harness?
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I'd make it, I've got a wee bit of experience with electronics, programming, & wiring. Been doing it for 40+ years 😉


Still need to come up with a DBC TB. I can't see spending big $ one one for a stock 6.0 with a cam. Thinking a stock OEM TB from eBay or local junk yard or a Chinese Amazon special 🤣
 
Joe_U4 said:
I'd make it, I've got a wee bit of experience with electronics, programming, & wiring. Been doing it for 40+ years 😉
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I'm trying to say that connecting can hi and can low to a sniffer isn't some custom voodoo.
There is no custom harness needed to sniff a Holley CanBus.
I'd be happy to provide you with a log file for you to decode if you so desire.

Joe_U4 said:
Still need to come up with a DBC TB. I can't see spending big $ one one for a stock 6.0 with a cam. Thinking a stock OEM TB from eBay or local junk yard or a Chinese Amazon special 🤣
Click to expand...
I would agree with that statement.
 
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