please step inside(ls2 SD tuning??)

[vette4beater]

I have been working on tuning my Gen-TTR 06 m6 ls2 gto for a while now.

i am running 2 Bar SD(maf fail set to 0) with the infamous "60#" injectors.
i just got the injectors set-up pretty good. 11.7 at WOT when in boost(atleast until my clutch starts to slip).

my idle is a little surgy, but i figured part of that would be taken care of with VE tuning.
i scanned for a while, filtered the AFR error%. when i tried to copy the histogram it wouldn't let me.

i got on here to see if i could figure out why. while i was reading i came upon this
http://www.hptuners.com/forum/showth...t=copy+afr+maf

So does this mean i should just give up and go buy an ls1? or does VE tuning by afr error % still work and only takes a long time to get right?

i also noticed that even with DFCO disabled it still spiked lean when i let off the throttle.

my non-boost afr errors are all +or- 10%, maybe i should just set it back to closed loop and just let the computer do what it does.

[EC_Tune]

It works the same even on the E38/E67 PCM's without a "normal" VE table. Just get them close and add a % or two when you are done to cover hot & cold days.

Post up your file & a log.

[5_Liter_Eater]

I'm actually not a fan E40 SD tuning. I too have the 2 bar SD OS but I actually went to a 100mm MAF and turned the MAF back on. Thats not to say it doesn't work.

For your SD tuning I would continue down the path you're going. Disable DFCO, disable closed loop (remember you need to max out both the ECT VS: Startup ETC AND the O2 readiness tables to disable both STFTs and LTFTs), clear fuel trims to ensure they are 0's and plot the AFR error agains the VE table(s) (primary and boost). The only thing I'll say is to do a multiply by %-1/2 to avoid overshooting. You need to be closer than +-10% IMO.

The lean spike may be due to offset/min pulsewidth tables not being right for your 60#'ers. Look up sjshafer's post about tuning 60# injectors for that.

[vette4beater]

thank you! i will continue SD tuning this weekend after i rebuild my vacuum pump.
i want to be alot closer to 0% error. i'm trying for +or- 1%. it just seemed like you were having trouble because it would go complete oposite instead of going closer to 0.
i will try a couple, if i can get it to copy the histogram.
or else i will adjust 1 cell at a time.


thanks
steve

[vette4beater]

here is my tune and scan.
can you see why my off throttle goes way lean, even with DFCO disabled?
why can't i copy my histogram for afr % error?

or else what do you think of the tune i'm running?

thank you!
steve

[vette4beater]

Here is a new shorter scan that i took today on the same tune.

i still am unable to copy the histogram for some reason!?!

[ktoonsez]

Need your cfg file, I can't see you histo's.

[vette4beater]

is this what you meant??

i had a hard time finding it. i had to re-save it in a new folder so i could upload it.

i hope it works, i really feel like i'm running in circles a little bit.

i also uploaded the tune, i made a few changes, it seems to run a little better but still surges sometimes and it goes lean for a little longer than i like between shifts and just into boost.

[Russ K]

I'm sure that you need to insert the user defined AFR Pid into the table display in order for the AFR Error histogram to function.

Russ Kemp

[vette4beater]

my afr error histogram works and it seems to be accurate except it has lean/rich spikes for all the cells.
i think i need to continue fixing my injector fueling and idle before i start messing with my VE tables.
i can't figure out why it surges on idle sometimes and why it goes lean for a bit when i shift @ WOT.

[ktoonsez]

You can't conpletely fix the momentary lean condition going from no throttle to WOT, the computer need time to catch up. To improve that, increase the "enrichment rate" on the PE tab to at least 1.5, maybe even max it out since you have a turbo or super charger. Remember when doing your logging to make sure you don't do any throttle movements that are too sudden when loggin the area's below WOT, move the throttle in and out nice and easy or you will get distorted data because the computer will have to constantly be trying to catch up (richen or lean out) with the new fuel requirments based on PE. Best thing to do is do some logging for the NON-WOT first (with no big sudden throttle movements) and get that area out of the way then do the WOT logging seperate ignoring the lower areas. Make sense?

[vette4beater]

yeah you make sense. thanks!
the enrichment rate is currently 1.5, i am gonna try maxing it out @2.0.
i plan on doing as you said with low range VE first.
i was just seeing how things were since my LTFT's were less than 10%.
i didn't like where my boost afr was lean at times i though it should go richer by 105 kpa. it looks like it has slow reaction for BE.

do you think changing the enrichment rate to 2.0 will help with that?
do you see any other fueling areas that may also help?

thank you very much!

[ktoonsez]

Yes the 2.0 is OK and will add the fuel quicker and remember that everything that is happening is ok, computer just needs time to catch up. I can't see the histo's that I want (#9 and 10) because of the custom PID you have. Post pictures of the screen with histo's 9 and 10 so I can see the percent errors and AFR. I noticed that you still have LTFT and STFT's enabled. You need to disable these when doing VE tuning because they are adding and subtracting fuel and you are not seeing your true AFR errors from the VE table.

You can wait on the screen shots since this data isn't really valid.

[vette4beater]

i wasn't scanning to do VE that time. i re-enabled the Fuel trims to see how far off they were.
i will try to scan again soon and will try to post the screen shots( if i can figure out how). i guess .cfg file from post #8 didn't help too much.

can you tell why my idle surges so much?
i don't think it's from the VE since it doesn't do it all the time. only when i am in city driving style.
maybe it is some kind of temp.relation?

[ktoonsez]

To do a screen shot, make sure that window has the focus and press ALT+PrtScr. Open up windows paint program and paste the screen shot and save it. You could also open the cusotm PID screen and save the PID's and try posting them and I can try to import them.

Surging, that can be a few different things. Usually can be tuned out with spark adjustments, sometimes with airflow. Try adding changing all of the 13's to 21's and then smooth the number up towards the upper right of the table in the "Idle Base Spark" table. Also add 2 to your "Final Idle Airflow Minimum" table from 1600 RPM and lower, but fix those 2 areas with zeros in them, not sure why they have zeros but that is not good, use the values just above them from the same column. Let me know if that works.

[ktoonsez]

Also, I remember my car used to do that with the STFT and LTFT's turned on so I just permanently disabled them and made my MAF and VE tables 3% RICH on the average for the areas I know the car stays in when I am cruising on the highway or in city traffic. That might be the answer in the end, especially if you have headers, they really piss off the narrow bands that control the trims.

[vette4beater]

i will try to get that done hen i get home from work.
thank you very much!

my turbo kit did move the narrow farther from the motor. the book i was reading said something about changing a delay or something so that they won't look for the adjustments they made to have an effect so soon.
i will try to re-read that part to see if i can figure it out.

it was engine management/advanced tuning by greg banish( i believe eficalibrator)

[ktoonsez]

I would be interested in that document to see if I can make my narrow switch a little better.

[SMOKINV8]

I'm pretty sure the delay you're talking about is the PE delay RPM.

Making the narrowbands switch better is pretty near impossible sometimes, but just remember that they need to be hot in order to work properly. Retarding the timing some at low/cruising RPM's can help with this, depending on how much you've already added in that area.

[vette4beater]

i think PE delay rpm is just to have it delay if it is below that rpm, which is currently set to 1500. this wouldn't cause a delay in enrichment when i'm WOT between shifts, i think.