Andreas,

Do you have to follow this process even if you disable LRA (NOLRA = 8, I think)?

If my rkat and fra are small across most loading, engine speeds, etc., I'm good, right?  Other than low load, low speed transient situations (1 second or so), my car behaves well.  Idle is perfectly smooth.  After the initial shift, lambda settles pretty quickly. 

I guess what I'm really asking...  Are there other lambda regulations than those shown in LRA (fra and rkat)?

John

*** Update ***

Feel like I'm making progress.  Current theory...  Porsche tuners optimized VAKL for DFCO, which explained why it had some very low levels - it wasn't actually used very often (DFCO forces error vales to be used when B_SA is set).  So, I set the VAKL and KFAVAK to the recommended values in the FR. Magitude looks good, but the short/long splits need adjustment.  Higher revs require greater short term.  In the process of logging and tweaking.

Still hung up on the cam change lean out...  See the attached log.  Could the 10% RL drop at cam change (which is confirmed by a nearly 10% drop in MAF) be triggering ESUK compensation that leans me out 10%?  If so, then maybe I need to drop short term decel percentage around 1,200 to 1,500 rpm...  Sounds like something to test in my next attempt.

Well, shit.  I thought I had this whipped (as outlined below), but I spoke too soon.    I'm still having lean out at some of the cam changeovers, about 10%.  So, I'm back to thinking I don't know wth the KFNWSL/H tables do.  Does anyone have an FR for the 996TT/ME7.8 or know where one can be had?  I'm not sure I'll figure it out without one.

I guess I'll have to look for alternative solutions...  One thought...  I have 2 tables, FKKVS and FKKVSNWS.  Maybe I could bump fueling at the boundary cells in each table?  Anyone else try this approach?  BTW, the Porsche factory tables don't appear to take this approach.  So, there's no evidence it'll work (if it did, then why do the KFNWSL/H tables exist?).

Honestly, the whole cam changeover could be an ESUK tuning issue.  As mentioned earlier, my RL and MAF drops during the change about 10%, which could be driving an poorly tuned ESUK response.

This is just baffling.  I'm kinda at a loss.  The factory ESUK settings are so far from the FR default values that I can't figure their strategy.  Example...  DUKK is 0.94 and ZUKK is 0.3.  When you couple that with a KFABAK short term portion of 0.2 (short term tip-in enrichment is only getting 2% of the total ESUK enrichment above TMOT of 60F), it sure looks like the Porsche calibrator nerfed the short term portion of ESUK, especially for acceleration.  Could it be that the OEM Deka injectors were that non-linear?  Or was Porsche just nerfing short term acceleration to smooth out the transition from decel fuel cut off to accel fuel cut-in?

Besides the cam change lean out issue that started this thread, I have one other lean out out issue that seems to be related to the weird ESUK settings, but this is just a theory.  DUKK and ZUKK effect both accel and decel. 

So, picture this...  You're in 2nd gear and accelerating moderately (60+ RL) -- quickly, but not enough to be into boost and your lamsoll is still 1.00.  Very typical street driving.  Then, you prepare to shift, lifting off throttle and your RL drops from 60+ to 18.  Since you've disabled decel fuel cut off, that load reduction sends lambda from something near 1.00 to the sensor rich limit (0.73) in about 0.4 seconds (because ESUK isn't doing shit due to the high DUKK value).  You press the clutch and shift into 3rd.  While you were doing that, ESUK and LR kicked in to correct the massive rich condition and put you in a slightly lean condition.  Then, you let the clutch out, applying moderate throttle (not enough for boost or a rich lambda target).  As you do that, you're starting from a lean lambda and ESUK isn't doing shit to enrich because the high DUKK is keeping it from doing so.  That causes your lambda to spike higher and you feel the sluggishness that lasts for a brief moment before LR and ESUK kick in to help get you back to a lambda of 1.00.  Sure, the car is driveable, but you know something doesn't feel right.

Assuming my interpretation of events is right, I'm left with 2 choices...  1) Enable DFCO at lower RPM, going back to factory NWEM settings, hoping the factory FUKE and ZUKE settings work for EV14s or 2) be prepared to change everything in ESUK from factory, which appears to be optimized for DFCO to low rpm settings.   Since I want to make #2 work, I'm going to set DUKK, ZUKK, KFBAKL/KFVAKL, KFABAK/KFAVAK to the FR values and test using the factory WFRL.  If that isn't a total disaster, then we'll see if WFRL tuning gets any easier.  Note that all my previous attempts at ESUK tuning only made things worse -- I'm hoping that was because of the high DUKK value, which basically undermined my attempts to address short term lean out in accel and vice versa in decel.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

***  Success ***

Hell yeah, muthafucka!  Finally, a cam change with no (meaningful) lean out! See attached log for proof.

Solution:  In ME7.8, KFNWSL governs mixture correction factor during cam change from late (retarded intake, zero overlap) to early (advanced intake, 30 degree overlap), BUT it isn't intuitive: Rich is numbers less than one, suggesting it might be a lambda-like approach or lambda-modifying value.  Since no available FR covers this table, I'm not sure exactly how it works, but I've confirmed that it does for my issue.  Word of warning: Do NOT set any values in KFNWSL above 1 or you will lean out (1.3 or more), usually in acceleration, and that is a recipe for disaster.

In my log, you'll see the cam changeover has been raised to 40+ RL from stock 22-23 RL level, based on advice from Mister T.  This actually makes the cam changeover lean out worse because the KFNWSL table values rise from 0.92 or so at the expected OEM point to 1.00 (no enrichment) at the higher RL.  So, contrary to intuition, raising the changeover RL makes things worse, if you don't also adjust the KFNWSL table.  In my test (shown in the log below), I reduced my 10% to 15% lean out (KFNESL value of 1.00) to 5% by reducing KFNWSL to 0.91.  So, the table seems to have a linear effect on cam changeover lambda.

I'll fine tune this with more testing and let you know if anything changes in the perception expressed above.

Well done

I remembered somewhere in the back of my head there being a cam change map, but didn't remember the name, and didn't have really time to look.

*** Update ***

New information...  
I did some very slow speed driving around the neighborhood in 1st and 2nd gear with a hot engine.  I found that I could recreate the cold lean out (issue that kicked off this thread) even when hot.  

What I noticed...  
1.  The lean out occurred without a cam change in many instances --> Cam change may aggravate the condition, but it isn't the root cause.  
2.  The lean out occurred under near constant load -->  Confirms transient enrichment/enleanment (ESUK) is not the root cause.
3.  The lean out always follows a sizeable ignition retard (e.g. 30 advance to 0 advance), even under constant throttle/pedal angle.
4.  The lean out only occurs in the region LLR is active, which is NSTAT (760 RPM Hot Idle) plus DNLLR (1,200 rpm), which means anything below 1,960 rpm when warm.  Higher when cold.
5.  The lean out occurs when operating near the idle RL (40% cold, 24% hot) in gear, rolling.  The higher value at cold explains why I encounter the problem more often when cold, but hot testing reveals the problem exists there too.    

So...  These new facts point to a non-optimal LLR.  

Thinking out loud...  I'll need to do more research, but my first thought is that my fully revised KFMIRL/KFMIOP (linearly scaled, like OEM) isn't playing nice with the stock torque reserve settings.  Since the torque vs relative load relationship is changed, the torque reserve tables probably need the axes scaled appropriately to mimic the stock behavior (which was fine).   If this doesn't solve the issue, then I'll raise the minimum ignition advance, which should be okay since my cat heating is disabled and there's no need to allow values like 6 degrees ATDC (as required by KH).  Side benefit to increasing ignition advance is less burbling exhaust on decel (which some might like).

Anyone else run into this issue?  Do most of you leave the low portions of the KFMI tables stock?  My first purchased tune for the car only altered the last 3 (high load) lines, perhaps to avoid the need to scale other items?  Maybe that is a better approach, but it must have it's compromises too (non-linear load torque relationship requiring KFPED custom tuning to avoid large load changes -- which my purchased tune did not have, explains why the pedal didn't feel "right").

Now, you tell me?  jk...  I've updated my IOP/IRL to be stock at 100 RL and below.  Definitely an improvement.

Do you typically leave stock up to 100 RL?  Or, do you start the scaling at a lower value?

The reason I ask...  Starting above 100 RL creates a very non-linear relationship between pedal angle and net requested load.  I'd really prefer a more linear pedal, but the limits of KFMIZUFIL won't allow for much correction in KFPED.  You're left with a pedal that is very sensitive at low load (not necessarily bad), but quite insensitive at high load (something I don't like).

How do you overcome this?  Or, do you live with a non-linear pedal?

PRJ,

I thought (perhaps mistakenly) that you should make sure KFPED requested torque stayed below the values in KFMIFIZUL to avoid torque intervention.  If you don't, then you end up with mifa (request) being set to the ceiling of miszul, right?  If so, you end up with something worse than an continuous, non-linear (pedal vs torque) curve -- a discontinuous, non-linear curve -- because actual torque can never become requested torque if that means actual would exceed miszul, right?

I guess if actual torque is lagging requested (like during accel), there could be no problem...?  Or, no problem if the engine can't achieve the requested torque (in a particular load cell), but then the KFPED design would be poor.  It doesn't make sense to me to request a torque that isn't possible...

Am I missing something?  Thanks in advance for educating me.

John 

Yeah I solved the cam leanout mostly through FKKVS as well on the dyno.