LSA LQ4 Tuning Help

[SiriusC1024]

Post the tune for that log, please.

[schiavonske1013]

Post the tune for that log, please.

Sorry about that, here's the tune file I used.

I do wish there was a way to convert transient fueling from Gen 4 to 3 to simplify that aspect, but Gen 4 uses IVT instead. Could copy the gain tables for evap and impact I guess as the tables match.

I changed my EOIT back to what the gen 3 calculators say to use as well, wonder if I should change that back to what I had previously where I converted the LSA EOIT into Gen 3 equivalent numbers.

[SiriusC1024]

You brought pressure back up to 58psi, right? Which wideband sensor are you using?

[schiavonske1013]

Yes I adjusted the pressure back up to 58, aem 03-0300

[SiriusC1024]

Doesn't look bad at all. You'll never get rid of all the transients. Retune and see how it goes.

[schiavonske1013]

And we're back, after the LSA injector install and base FP brought back to 58 psi, I learned a hard lesson that despite knowing there can be fakes, and being careful and reading and checking reviews, you can still get a set of knock off NGK spark plugs off of Amazon. No one locally had any TR7s, so I said fuck it and tossed in a set of TR6IX. People seem to be running these at decent boost levels without issue.

I know I keep beating a dead horse, but after the injectors and legit spark plugs, the transients improved a bit, so I said screw it and started messing with injection timing, I ended up setting it to match stock EOIT from a CTSV stock file and the lean tip in has become unnoticeable in gear, I can hit the pedal at any point and it's just instant throttle response. Free revving in park it's barely noticeable to the point where I will likely leave it alone.

I ended up reading a thread about ETC area scalar and ended up formulating my own based on something I read, by increasing it a bit the return to idle is much better. Still some work to do, and how much of that can be attributed to the stock injectors I can't say, it still dips low, but not as often, and it catches much quicker and is much softer.

More importantly it runs infinitely better. Need to work on the closed loop portions, and boost in rich, but it is much improved in terms of drivability in all areas. I did noticed duty cycle up past 100% by a bit, however I'm hitting 10.9-10.4 AFR so I need to lean it out a bit. Anyone opinions on if getting fueling more dialed in will drive my duty cycle down enough to not be as worried?

Also the knock retard wasn't during a power run, it was when I decided to let it shift into 4th and lockup the converter where it showed up a bit.

Tune and log attached, appreciate any input.

[schiavonske1013]

Not to be a bother because I know there’s a ton of people who need help, but anyone have any comments on the duty cycle? I’m working on dialing fuel in closer, but wanted to get opinions on if I may run into issues further down the road. I know around 80% is the recommended safe zone.

[edcmat-l1]

What is "up past 100% by a bit"? If it's 10.9:1 now and you target 11.5:1 you'll only drop about 5-7% on your duty cycle, roughly. So, if you're 110% now you'll most likely still be over 100% @ 11.5:1 AFR.

[schiavonske1013]

I believe the highest it got was 102.5%, afr was I believe about 10.7 with a commanded 11.47 at that time.

[schiavonske1013]

Finally getting close to dialing everything in, when doing a full throttle pulls I noticed that my EQ ratio seemed to go a bit leaner on my 2nd run over the first, I was about 2-3% richer than commanded at max kpa/rpm on the first, then the 2nd run I was 5% lean at the same kpa/rpm. I realized the difference was IATs, on my first run I was around 86 degrees, where the same spot in the VE table on the 2nd run 102. I'm in SD, running the IAT in the lid on the LSA, stock LSA sensors which research seems to show has the same settings as the stock truck IAT in the MAF and no changes to the table were needed. I have the complex temp model disabled per the notes in Editor. Is this a matter of the PCM pulling more fuel for hotter IATs than it should? Is there a way to dial this in? Most threads recommend messing with the complex model, but being disabled this won't really do anything unless I reenable it. My initial thought was use the hotter percent error and live with it being a bit richer when colder, but my bigger concern is being the northeast where it's 40 degrees, once summer hits and it is 80-90 outside I know my IATs will climb even more.

EDIT: Forgot to mention, cruising IATs are around 20-25 degrees over ambient, I do plan on some HX upgrades, but even with that, during summers my IATs will definitely sit over 90-100 constantly.

[schiavonske1013]

Just wanted to reply to bump this up to see if anyone had any insight. Haven’t been able to do much tuning at all as I’ve just run into one issue after another will random things breaking and little time to fix it, but that’s what I get for using a 250k mile truck as the base for the build.

I know heat soak is an issue with these especially at idle and on restart, and I know under boost especially iats will rise pretty good especially in the summer, I guess I’m just worried that there is some type of setting I am missing where the pcm is pulling too much fuel or something as Iat rises. I’ve seen some mention on other sites of Lsa swaps where people didn’t even use the lid sensor and instead used the sensor at the air intake, but this seems like a bad idea?

[SiriusC1024]

As far as IAT and boost the best thing to do is have the IAT in the manifold and disable the Complex Temperature Model.

[schiavonske1013]

Alright that’s what I was figuring and how I have it set up, wanted to make sure I covered all my bases. I’ll just have to keep an eye on it as it gets warmer is the solution I assume?

[SiriusC1024]

By disabling the model you remove any accounting for air being heated through the intake tract. You're telling the SD model that the temp of the air is the actual IAT reading. Won't have to keep an eye on it as weather warms up or cools off. There should be a port on the LSA housing for it.

[schiavonske1013]

Alright so at least I did that right, and I do have the sensor in the lid. I’ll see if it continues.