Tuning my 04 suburban quadrasteer

[quadraburb]

got rid of my idle to throttle on knock by lowering the idle timing a bit. however I'm still getting random 6-8 degrees of knock retard on part throttle.
I'm noticing that in almost every case the wideband is reading lean, by quite a bit.

not sure what is causing that, but I'm reading through causes in the forums. attached is the current tune and a log, you can see a few areas of repetitive knock while I was getting on the highway. the VE table is a bit sloppy again, I was making adjustments and trying things out.


Edit: went and redid a lot more stuff from reading

1. went back to the stock low octane map for the 6.0. had a 5.3 low octane map on there for reasons involving ignorance.
2. knocked the timing down, and slowly started bringing it up to about 6 degrees higher across the map.
3. adjusted burst knock to be less invasive temporarily so that I could see the actual knock feedback
4. redid overspeed and underspeed idle timing for a smoother idle. (i keep playing with this, but its not important)
5. redid all my injector data using a function someone made in excel to convert gen 4 flex fuel data to gen 3. there wasn't much difference except for a change in injector pulsewidth, this was pointed out by another member as well, but im a moron. this may explain going lean on tip in as that would affect things.

no knock aside from 1-2 degrees on transient.will upload tunes when i get a moment.

[5FDP]

Burst knock should be off if you ask me, I never leave it on with modded engines.

Not that this a tip in knock problem but I think your PE fueling is too lean, I don't even run my direct injected engine at 12.93 on pump gas, only E85 would I go there. I error on the side of caution and run 12.3-12.5 on an engine like yours.

Looks like it wants more fuel down low as well, some of your cruising areas are lean. The VE look a little low.

[quadraburb]

Burst knock should be off if you ask me, I never leave it on with modded engine.

I agree, and zeroed it for todays revisions.

for searching eyes sake, the burst knock is a calculation, not feedback. if the throttle opens and cylinder airmass crosses a certain rate of change it will pull timing to protect against potential knock, a lot of people tune it to be less sensitive, when I turned it off my throttle on knock readings went to zero.

Looks like it wants more fuel down low as well, some of your cruising areas are lean. The VE look a little low.

attached is the latest revision, I manually bumped up the VE in the lower ends and lowered the upper end, going out for a MAF rescale and VE tune today.

In the log there is one point of steady knock at 5-7 degrees. I knocked the timing back and smoothed out the table in that area.


Also attached is the injector conversion file that I used for the 12613412 injectors.

[quadraburb]

updates:

burst knock off.
higher VE on the low end, requires more smoothing and scaling.
adjusted fan kick in temps and speeds
raised idle timing
raised WOT timing by 3 degrees
pushed mid range low RPM timing down by 2 degrees.
turned off LTFTs entirely, running purely STFTs from now on.

things are looking a lot better and the truck is waking up

[quadraburb]

380 mile trip on the highway. unfortunately i hit the wrong button and cleared my log before I could save it.

fixed a whole bunch of issues
1. used bluecat to tune the shift points in normal mode.
2. widened shift points in performance mode and cut shift time down
3. reversed PE ramp in time to be instant.
4. added more fuel to VE table
5. added more air to MAF
6. revised idle over and under timing
7. revised cranking fuel
8. revised burst knock settings as it was pulling a consistent 8 degrees because i had put the wrong data in

had a few issues with the PE suddenly going to .93 and not moving, I found out that I had made too much of a change in the VE table and it failed the MAF with a p0101 code. oops.

I'm still playing with the DFCO to try and get it to shut off entirely when coasting. during coast on the highway the throttle sticks open a bit and the engine seems to just run at a low state, at least the injectors are indicating its still running. currently reading and searching on what others have done.


lots of work to be done in the mid range with timing. in areas of high air mass and low RPM it starts to knock. however at the upper end its still taking timing.

[quadraburb]

Had more time to dig into the truck.

big changes include:
DFCO finally works, didn't think about the fact that the cam is less efficient at lower RPM, thus the activation threshold for the MAP needed to be lower.
modifying the knock sense vs cyl vs rpm table at about 1600-1800 RPM as it was registering false knock.
adjusting the blue cat trans table output for lockup, I dont want it going into lockup around the mountainous areas I live in at 45-55 mph, it causes too much lugging.
more spark at highway cruise, and more spark in deeper throttle regions.
revised VE and MAF again, I was tuning at 600 feet msl while at works and then realized my truck spends most of its time around 1600 feet msl in the mountains.

I pulled a load to see how it would do, given i live in the mountains this meant pulling 6800 lbs up a steep hill for 1000 feet. it held up pretty great, but its clear I need more timing and fuel in some areas. also lowered the PE enable.

The false knock has been driving me crazy, I found a few culprits which cleared up a lot, but ultimately I gave up and desensitized the knock sensors on the cyl vs rpm table. I tested for false knock by reducing timing to almost zero in the area it was registering (1600-1800 rpm at about .48-.70 cyl airmass) and was still getting 8 degrees of knock retard even when touching the throttle.

things are looking a lot better, still could use more fuel in some areas, but its not giving me as hard of a lean spike on throttle on anymore.

[LQ9408]

Under the Fuel tab>Power Enrich>Enable> Min Torque, zero that out. It eliminates an unnecessary variable that slows the activation of PE. Second thing, Airflow>Dynamic> Dynamic Airflow>High RPM Disable, set it to 8,000 RPM.