5.3 "LMG" swap, getting a E38 started, fuel economy

[harascho]

Here are two of my first logs. As I explained in other corners of this forum I have a 1997 Tahoe with a 2007 5.3 LMG, 4L60E, E38/T42 combination.
Beside some other problems the fuel economy or lets say the nonexistent fuel economy is a thing I have to work on.

As my knowledge of tuning is still in a steep learning curve I may need some help to interpret what I recorded on the testdrives...

I took the opportunity to take my tahoe on a longer trip. I had to drive to the south of Germany. It was about 200mls, a forth of it through some small towns and country roads, the rest a longer stretch of our autobahn. I set the cruise to 70mls/h and watched the AFM working. It only kicked in when the road went downward (very little was enough to get V4 mode) .As soon as the road was flat I was back to V8 mode. Without the cruise it felt that the slightest movement of the throttle and I was back in V8 mode. I think there is room for some refinements so that the V4 mode is kept longer even with a little throttle applied.

The overall fuel consumption was 13,7mpg which is what I think very high for that very careful right foot.
what could be done to get better milage out of a e38 controlled LMG 5.3?

Is there a way to get a kind of lean cruise mode? Could I tweak the calibration to get more miles out of a gallon? Ideas to widen the V4 zone where adequate..?

To the logging of the important PID's. What should I keep an eye on when I am looking for a better mileage?? Could there be something wrong in my application ?? The only thing I see is a strange TCclutch slippage, like a sine wave (30 - 80rpm)
The fuel consumption Patrick and Vegasrobbi report are a whole different story.

best regards and thanks for your help

Harald

[GMPX]

I suppose the first step would be to figure out why AFM is disabled so easily (remember the new PID).
There is no Lean Cruise at all, that was gone since the E40 came out.

Cheers,
Ross

[gmtech16450yz]

Lower numbers in B0950 will let AFM come in easier (at a lower vac).
Lower numbers in B0951 will let it stay in 4cyl easier (takes more of a vac drop to come out of 4cyl mode).
Raising B0960 to 8 or 10 will make it less likely to come out of 4cyl mode because of tps.

Make sure you're getting as much timing advance as your fuel will take. Don't expect much, a certain size motor making a certain amount of hp moving a certain size weight at a certain speed will get a certain mpg, period. You can move the numbers up or down slightly but not much. Don't believe all these guys that say "my mileage went up 2 or 3 mpg after I put my CAI on". I've got 30 something years of logging and trying to change mileage in hundreds of vehicles and here's what I've found... it's pretty easy to increase performance, driveability and throttle response but it's very hard to effect mpg. What usually happens when tuning for better efficiency is you get more hp and torque and it doesn't LOWER your mpg. Most likely because you just end up using more of that hp.

FWIW, I've been looking at the DIC average mpg on a large percentage of the 6.2 Denali's I've been working on for the last couple of years, just to see if there's a common number on all of them. After looking at them for awhile I realized there was a pretty solid common average- 12.6mpg! Some of them had never had the average mpg reset so they show the average over 30k, 40k, even 50k miles. (you can tell by the gallons used when they reset it.) The biggest factor on that mileage is AWD, or 4WD. You're going to get at least 1, maybe 2mpg less with 4 or all wheel drive.

Sorry for the long post. My advice is keep the AFM settings stock, run prem fuel always and get your timing as high as you can. Oh and if you have a steady foot, you will get better mileage if you don't use your cruise control.

[harascho]

Don't expect much, a certain size motor making a certain amount of hp moving a certain size weight at a certain speed will get a certain mpg, period.

You are absolutly right with this. But I know my driving habits and when cruisin' with a 2001 Suburban 4wd in CA including a trip to Death Valley with the AC running I could manage to get about 16mpg. And I could repeat this several times.
So the Suburban is a whole different thing than a 2dr Tahoe.
Did you look at my tranny log? That strange sine wave of the TCCslip PID? Is that normal?
My problem is I don't know, do I log something odd or is it just quite normal. Also the timing and the fuel trims in the other log, could they be called normal?

Harald

[joecar]

Harald,

I now think that that much tcc slip is not normal (thanks to discussion with jfpilla...:cheers:...and review of some old logs)... since TIS:TOS matches the known gear ratios, the conclusion is that the tcc is slipping...

Also, something else that looks wrong is TCCMODE... this is showing "Slew" most of the time (instead of "Locked")... I don't know certainly, but this doesn't look right.

In addition to those pids, also log other pids like TCCDC, RPM, VSS, GEAR, TFT, ECT, IAT, MAF, MAP, TFMPRS, MFTOTAL (misfires).

Cheers
Joe

[harascho]

In addition to those pids, also log other pids like TCCDC, RPM, VSS, GEAR, TFT, ECT, IAT, MAF, MAP, TFMPRS, MFTOTAL (misfires).

I'll do my very best, but when logging T42 stuff I cannot log E38 PID's at the same time.

To the tranny , I hope to find something in the tune files 'cause the tranny and torque converter where almost new, they had 9miles on them and this proved to be true... (engine had 6miles....) So we are talking about a real new engine and tranny.

here are the pid and dash I prepared for logging tomorrow

Harald

[joecar]

Oh, yes, I forgot about not being able to log 2 modules simultaneously...:doh2::doh2:

[joecar]

Those pids are sufficient.

[harascho]

I went through the T42 TCC parameters and found only the apply/release/and pressure settings.
I could not see anything about the TCC mode when it should be locked when it is in slew mode...etc.

Did I miss something or should I dig into the E38 tune?

Harald

[gmtech16450yz]

"Slew" during lockup is normal. Don't know enough about it to tell you why though.

[harascho]

Hi friends,

I had the opportunity for some logs.. engine, AFM and TCC

With the tranny section, I found that when the TCC locks (very rare) I have higher TCCslip rpm's ( 100 - 300rpm) at a TCCDC of about 10 - 15% compared to the slew mode with only 30 - 40 rpm TCCslip and a TCCDC of about 40 - 50%. This looks a bit weird for me?
I thought when the TCC is locked we are talking about 0 TCCslip rpm?

To the AFM log. I tried to figure out what throws me out of V4 mode.. most of the time it's the AFMA 31 (Manifold VAC) and or a combination of AFMA 31 / 20 / 18 (Gear shift in progress / min time V8 not met)
Also the MANVAC gauge in my dashboard is a bit strange... with a little throttle it changes from 0psi to 94PSI I think, there is something wrong either with that PID or my gauge. Strange is first it was not valid, but the gauge wasn't crossed and worked??

Then the engine log. The spark advance changes a lot from 30 - 40 to lower values ( 0 - 10), I recorded some MFTotal but for the rest my knowledge is too small.

Whast pops up in my mind is : could I have a manifold leak somewhere? With the AFM kicking me out of V4 mode with that very little change in TP ??

Maybe one of you has an idea..

My Tahoe has to stay outside this night. I had to pull a friend out of a ditch with high snow. I got him out but now the Tahoe sits at a quite interesting angle in that ditch against a fence. Even my tractor with 4x4 wasn't able to pull the Tahoe out. We will try it tomorrow morning with some bigger stuff ( a big woodpicker on chains...)

Harald

[gmtech16450yz]

Here's a couple clips from some TSB's, might help a little...

Review the snapshot while watching TCC slip speed while at constant throttle. If the slip speed cycles from approximately 0 to 60 RPM in a fairly even frequency the transmission is operating normally and is reacting to variation in the engine RPM. This engine RPM variation is more evident between 1100 and 1500 rpm, with a green engine with low miles, and will be worse in higher ambient temperatures and when regular fuel is used rather than the recommended premium fuel. Make sure the vehicle is using premium fuel and allow at least 5,000 miles to accumulate before re-evaluating this condition.

When TCC is enabled slip speed may momentarily go to zero but should increase to 20 rpm or greater and should not remain at zero. If the TCC slip speed remains at zero remove the valve body and inspect the regulator apply valve (380) for freedom of movement in it's bore.


I'll look at yours and my trans logs tonight when I get a chance. I think what you're seeing might be ok or normal. Stock AFM settings also do make it come out really easy on accel, usually it only stays in on decel or on a totally flat road with no load or a little tail wind. Slight headwind and you won't be able to maintain 4cyl with stock settings. I don't think people realize how much the wind effects these trucks and SUV's on mileage and things like AFM. (I don't mean you specifically.)

[gmtech16450yz]

Ok I do very little tranny work so I'm not an expert, but here's what it looks to me is happening. Maybe someone that knows more than me on tcc can help you more or let me know if I'm figuring this right...

When the tcc mode pid shows "off", the tcc solenoid is open and lets pressure out of the clutch, keeping it disengaged. When it goes to "lock" the tcc solenoid closes and keeps fluid in the clutch, but at the same time the tcc pwm valve goes from 100% to 5 or 7% or so. High percentage numbers on the pwm solenoid is full flow, low numbers are low flow. With the tcc solenoid holding pressure in, the pwm solenoid starts to increase flow going in until about 50%, which is enough to keep it from slipping but not totally locked. If you give it more throttle but not too much to drop out of tcc, you'll see pwm percentage go up, I'm assuming to help keep the clutch from slipping too much. This tcc solenoid closed/ pwm solenoid controlling input flow and pressure is "slew" mode. On decel it looks like it just drops the pwm duty cycle which makes the clutch release, or slip.

Now I'm just ASSUMING all this, I didn't read up on any of the actual tcc operation descriptions or fluid flow charts and I'm not a tranny guy, but I think this is right. So from this assumption, I'm wondering if you put the minimum pwm percentage at 50% or higher, the tcc would lock immediately when the tcc solenoid closes, just like the older tcc systems used to work. If the tcc solenoid stays closed on decel, keeping the pwm valve open would keep the tcc locked on decel. I believe if you put the minimum pwm percentage higher, like at 20 or so it would engage faster and slip less, but I'd be afraid in situations where tcc solenoid is closed and it's trying to disengage tcc strictly with the pwm valve it may partially drag the clutch and cause damage.

The other thing I noticed on my particular truck is tcc slip speed above 50mph steady throttle is pretty much 0 +/- 5rpm. Your max speed was only 45mph so I can't really tell if your slip speed is comparable or not. Try another log at sustained freeway speed, and log tps too.

[harascho]

I will try to get some quicker runs tomorrow. What you posted from the TSB's seems to be the situation I have.
Your explanation of the TCCmodes makes sense. Lets see what I can log tomorrow.
If all is close to normal I am wondering where all my fuel is going to...;-))

Harald

[joecar]

Harald,

I don't think 40%-50% TCCDC is sufficient to hold the TCC... (my $0.02).

TFT at 117°F seems low (around 160°F-180°F is considered operating temp)...

Can you take another trans log when weather is warmer (see note below)...?

From what I had previously seen, "slew" (with a mid-range % DC) was usually commanded to apply/release the TCC in a smooth/imperceptible manner (unnoticeable to vehicle occupants)... so I don't know if what you're seeing is correct or incorrect (maybe it has to do with what the TCM does when TFT is low...?)

I know GM have made some torque converters containing a viscous fluid clutch instead of a TCC, the the controller for these adjusted the % DC continuosly, but I don't think the viscous clutch ever made it into the 4L60E/4L80E torque converters.


note: when you next log trans again, please add TIS (in adition to the pids in your 200209_Tranny_1.efi (http://forum.efilive.com/attachment.php?attachmentid=4758&d=1235158060) in post #11);

also please add TP if it shows up on the TCM.


RPM
VSS
TP
GEAR
TCCMODE
TCCSLIP
TCCDC
TOS
TIS
TFT


Thanks
Joe
:^)

[gmtech16450yz]

I don't think 40%-50% TCCDC is sufficient to hold the TC...

TFT at 117°F seems low (around 160°F-180°F is considered operating temp)...

Yeah I know both of those sound weird, but they're normal. Mine does stay locked solid (less than 5rpm slip speed) at 50% duty cycle. And trans temps on these (at least with the optional trans cooler), are usually really low. Mine rarely gets to 180.

Just checked one of my trans logs, I'm showing 0 slip speed at as low as 40% duty cycle.

[joecar]

Hmmm... so it's not TFT dependent.

[gmtech16450yz]

Yeah just drove about 30 miles and TFT went to a max of 127 degrees.

Did notice something very interesting though, TCC slips constantly when in 4 cyl mode of AFM! Looks like yet another reason I'm really leaning towards less 4 cyl mode is better. You guys that are setting up AFM to stay in 4 cyl mode under heavier loads might be paying for that fuel savings in torque converters.

I made the second half of my 30 mile drive with tcc pwm minimum percentage at 50%. It did exactly what I thought it would do, tcc acts more like it used to do on older cars and trucks. You can feel it come in and out because there's no gradual slip when engaging and disengaging. (Or at least the slip is quite a bit less, it still slips a little.) In AFM the slip speed is 0 +/- 5rpm, instead of 40-50rpm with stock min pwm settings around 7-15%. It was a little harder to keep in 4 cyl with the added load of a locked converter (my AFM settings are pretty light.) I don't think that's why they want it to slip though, I believe it's to lessen the vibration of 4 cyl mode. Not sure I like that, I'm keeping my 4 cyl mode only coming in on decel and super light accel. Timing in 4 cyl is pretty hard to get any more advance out of already, I would assume if you keep the tcc from slipping in 4 cyl it would also make it more apt to get into KR even at stock timing.

[harascho]

Joecar, remember? :

Harald,

Can you feel it only at low RPM, or at higher RPM also...?
What does engine RPM look like compared to TIS and TCCSLIP...?

>>> oh, you know what I just realized...
The 4L60E does not have a TIS sensor... the PCM/TCM computes TIS from TOS (VSS sensor)... so TIS:TOS will always be correct... I am sorry, silly me (slap me now...)...

Collect some more logs... include VSS, RPM, TP, TCCDC, TCCMODE, TCCSLIP, GEAR, MFTOTAL (misfires) [or the equivalent pids for your ECM/TCM], and a few others.

Joe
Quote

So I think, logging TIS doesn't make a big sense here?

Harald

[joecar]

Harald,

By having TIS I can apply the calc pid "RPM - TIS" without having to multiply by the ratio of current gear (like this: "RPM - TOS * Lookup(GEAR, 1, 3.059, 2, 1.635, 3, 1.000, 4, 0.696)"...I am not sure this would work right because the starting state is not 1... or like this: "ROM - TOS * BOXRATIO"... I don't think the BOXRATIO pid is available on your TCM...?).

I wanted to compare TCCSLIP with "RPM - TIS" as a sanity check...

see the attached calc_pids.txt.

Regards,
Joe
:)

[harascho]

Hi Joecar,

I will do the logs tomorrow including the TIS PID. I will go down the autobahn to get some data from higher speeds. Here where I live it is almost impossible to get a steady run for a few minutes at 50mls/h or more.
Up and down, left and right all the time..

Harald

[harascho]

I did some quicker runs today and found some interesting stuff.

First log.....TCC behaviour:

ervertime I was above 60mph the TCCmode was "unknown" and the TCCslip was almost 0 rpm. In slew mode it was app 30 - 60rpm. I didn't see the "locked" mode any longer than a few seconds. Most of the time the mode was "unknown" at higher speeds. The VSS (listed as condition in the PID selection, I built a gauge for it in my dash..) was about 20 - 25mpg lower than the actual speed the speedo showed.
My tranny fluid temp is extremly low even after this quick run , it was max 130F. ( I have a radiator tank cooler plus an external cooler and an additional external fluid filter..maybe this is overkill..?)

Second log...engine:

I was up to 90mph and logged all the vital data.

Third log........AFM:

I logged the fuel status PID and all the AFM PID's to get a better impression what throws me out of V4.

Forth log.......spark:

I tried to log the related PID's to see if any condition is substracting from the base spark advance... I cannot see something special.

as usual any ideas are very welcome..

Harald

[ScarabEpic22]

I wouldnt worry about the trans fluid temp not getting above 130F, I have an external cooler on my 4L60E and even after my 300mi trek home the highest temps I saw were 130-135F. In the summer they're more like 160-180F.

[gmtech16450yz]

Hey Harald, I took a quick (really quick) look at your logs, a little hard to tell with 100% certainty because some logs had too many pids and others not enough, but here's my 2 cents... Oh don't worry about the pid selection, you'll get better at knowing exactly what you need to look at. At least take out the ones that aren't showing any data and if possible (usually is) keep the channel count at or below 24. You're usually going to need pedal position (APP), rpm, mph (VSS), timing (SPARKADV), MAP, KR (GM.KR), torque reduction spark retard (SEMRET), fuel system status (FSST), airflow grams/cyl (APCYL_DMA), delivered torque (TRQTRANS) and commanded throttle actuator control (TAC_PCT). There's plenty others obviously but those are some of the more universal ones that you'd need checking most areas of your tune, just add in the others like fuel trims or different spark pids, etc that you need when you're trying to nail something specific down.

It looks like there's a lot of potential in your timing, you shouldn't be going negative, and you should be able to bump it up quite a bit at least at the light load end of the high octane table.

I couldn't really tell much in the AFM log, like I said before you'll need to change the vac tables and tps% if you want it to stay in easier. Bump timing a couple degrees in the AFM high octane table too. I personally would keep AFM settings stock, I don't like the idea of trying to pull around a 4WD Tahoe on 4 cylinders, especially at higher speeds. At low speeds AFM just makes the motor lug down so it's pretty annoying. (Again, my personal opinion, feel free to take it or leave it, you won't hurt my feelings!)

Your trans/ tcc log looks normal to me, at least what I can see with the pids you had. It's not locking at lower speeds (below 40mph) but that's the way it's set up stock. You don't want tcc at speeds that low, and certainly not locked solid. At high speed it looked like it was locked solid, like it should be. I would raise tcc engage and release speeds, but that's just my personal preference. I don't like lugging the motor down low, just too hard on main bearings and you have to give up too much timing.

Not much but I hope that helps.

[joecar]

Harald,

Very interesting, this trans log contains extra detail (thanks):

TCCSLIP goes to zero when TCCDC goes above 55% (in two places in the log)...

You can clearly see the "slew" action (TCCDC ramps up).

I am puzzled by the multiple slew states...

I agree with gmtech's recommendation to raise the TCC locking speeds... with your low TFT's you won't have any problems.

lol... CALC.SLIP is very close to GM.TCCSLIP... :hihi: ...so the TCM is doing a good job on computing slip rpm.

Joe

[harascho]

I
t looks like there's a lot of potential in your timing, you shouldn't be going negative, and you should be able to bump it up quite a bit at least at the light load end of the high octane table.

Hi alll together and thx a lot for your ideas.

I took a look at the spark tables in my tune..... I was shocked... I had to leave the computer to get me a cold beer.. drank a glass and took a second look... oh boy...
Where should I start advancing the timimg? Where is the light load end at all ?? And how did you experts start a task like this...

I tried to compare the high and low octan tables... I cannot see any difference at all??

I won't change anything this night... just read a little more in the forum and enjoy my german beer....
Maybe someone has a little more detailed input for me?

Harald

[harascho]

thanks to Vegasrobbi I am on the way to improve timig, AFM settings and the TCC.

I advanced the base Spark tables (low/high octan and low/high octan AFM)
10%, (AFM 5%), then 20% (AFM 8%) . Then I adjusted both AFM VAC tables -10% and raised the TCC rpm by 10%.

Just to have a baseline to start with.

The first drive this morning to work showed the AFM kicking it a little earlier and it stayed in a little longer. With a very light right foot I could keep V4 mode even with a little throttle applied (very little..) . I will try to get this to work perfect with my normal driving habits.

The raised TCC rpm's were also noticable, I am quite happy with the new settings.

To the spark advance: I will do some logs on the way home ( created a table KR (rpm / aircycl) and then I will see if I can give the basic spark tables a little more advance than the 20%.

Strange is, all 4 basic spark tables were the same. Is that the normal setting?

best regards

harald

[harascho]

I did as Vegasrobbi described


What I did is:
Choose a table, click in the top left box which selects the entire table.

Go too the small box used to change the table parameters, put in "10".

Move to the right and click the "%" sign, this will increase all cells by 10%.

If you put in -10 it will decrease the selected cells by 10%.

Then I went to the scan tool and created a map. Knock Retard is the data. Choose the same pids used in the spark table, RPM and Gr./cyl.




but ended up with many cells in the KR map with knock activity. Should I adjust the spark advance 'till no knock is present in the map? (I set min value to 10) I also see knock activity with the unmodified tables. ( low air/cyl cells)

I then did some other mods to the spark tables.

the 4 tables are not equal, they only look similar at first glimps.

First I let the AFM tables as they were. I only adjusted low and hi octan. And I try do do the same mods to both.
as of EFIlive:

B5101 defines the upper timing when good fuel, with adequate octane is being used, and the engine is not in an idle condition.
The ECM interpolates between the high octane map and the low octane map values based on knock activity.

So it makes sense to adjust both tables at the same time. I think the goal is to raise both.
But we have to be careful. If you select the complete table and try to raise the spark advance by 20% the initial negative values at low rpm and high air / cyl. will be even lower (more negative as they were before..) So I think the neg values should be adjusted -20% the positive values +20% to raise the overall table by 20%

I hope I got this correct?

which values for KR in the map rpm/ air per cyl are acceptable?

I know.. more and more questions but I am bitten by the bug of tuning...

Harald

[gmtech16450yz]

You're KR looks very low so far, except for the 3.7 degrees in the first log, there's almost no knock retard. The timing still looks pretty low overall. I don't like the idea of changing spark tables by a percentage, here's why... If you go 10% across the whole table, values like 55* are going to go up by 5.5*, which may be too much. Values like 5* are only going to go up .5*, which in no way is enough. I would suggest adding about 5* to the entire high octane table for starters (assuming you're using prem fuel), and leave the low octane table stock for right now. Unless you're getting a lot of constant KR you're not going to be into the low oct table anyway. (Log octane scaler to see if it's staying in the high oct table.) Best to leave it low for now in case you do go too far on the high oct table.

Min final timing (B5157) will set the min timing, you can try setting it to 0* over the entire table for starters, you really don't need to be going negative and 0 is a safe setting. Alternatively, you can just take all the negative numbers out of the high octane scale, but min timing will override TM retard, etc, which is nice to have an absolute min setting for all situations.

Have fun!

[harascho]

so here is what I will try after work....(06:46 over here.. office time..)
I will modify only the high octan table by +5deg through the entire table.( The adjusting by % is not the best I understand..)
With the +5deg there will be still a few neg numbers in the table but I will leave them as they are then and will set B5157 to "0".

I will also log the octan scaler to see if it stays in the high octan table (I am using prem fuel 'cause prem we call it "super" and "normal" are the same price in germany..)

To my KR map and the parameters rpm and air/cyl. Do I understand correct, that the cells are just counting any knock? or knock retard by deg?

I am not sure how to interpret the cell values..

Harald

learning how to tune is fun... and you see progress every day... thanks to you guys..

[harascho]

ok, I advanced the high octan spark table by +5deg (Spark_1)throughout the table and set B5157 to 0. I also added the octan scaler to my PID list.

First run was with the +5deg setting

Second run another +3 degree (Spark_2) added to the high octan table. (total +8deg)

I have to admit that the second run had a little more load on the engine, I had to drive up a longer hill.
The summary is about 3deg KR and about 6 deg KR in the two runs.
I watched the KR map but I am still not able to interpret that cell counts. Is each count a knock retard? knock retard by xx deg?
The octan scaler was 0 . That means I was running the values of the high octan table all the time.

How should I proceed? reduce spark advance in certain cells..?

Harald

[joecar]

I watched the KR map but I am still not able to interpret that cell counts. Is each count a knock retard? knock retard by xx deg?

Harald,

Regarding the KR map: don't view cell counts... instead view cell maximum values.

Joe

[harascho]

I have no idea how to change from cell counts to max values....

the maps properties don't show the max values.
Then next question, if I see the max values...which should I consider too high and retard the timing in that cell in the high octan table..

harald

[harascho]

I only see ( if I switch on the display type) the average values of the cells. That's what the name of the map says.

But if I take a look at the cells it must be the counts, 'cause values from 2000 - 4000 in some cells won't be the average KR retard in deg..

Harald

[harascho]

ok... got it..... don't read my last two posts......trial and error I finally gave that map commands a close look..... I am stupid..;-)

max values are around 6 in two cells..... which level in some cells is acceptable? The tables empty count is 10. I only have 13 cells with some knock retard at all....

I should start a better test run tomorrow.

When I have a better log..the only thing left is should I adjust the spark table to no KR or is some KR acceptable?

Harald

[gmtech16450yz]

There's an up arrow symbol next to the X and the N on the map page, it says "show maximum cell values". Click that and it will show you the max KR in each cell. There was a ton of KR in the second log. 6.6 degrees, that's too much, back off on those cells at least 4 degrees and see what happens. It's mostly at 1400 and 1600rpm, you might also help keep some of that from happening by raising shift points a little to keep it from lugging down when you're pulling grades.

Yeah, just looked some more, it looks like you're in 4th gear at 40mph, that's too low (IMO). That poor thing is trying to accelerate from 1300 rpm in 4th gear. Even at 18 degrees it was getting 6 degrees knock retard. Raise all your upshift and downshift speeds (and TCC), you can try 5mph as a ballpark number for starters.

Oh and the octane scaler was incrementing, it was at .375 towards that end of the second log, that's almost half way into the low octane table. That's why it's a good idea to keep the low table stock while you're messing with the high oct table.

Hope that didn't sound like I was picking on you, we all know the learning curve is steep, you're doing great and most of all you're having fun!

[gmtech16450yz]

no KR or is some KR acceptable?

An occasional 1 or even 2 degrees isn't terrible, if you notice they're always in a particular cell then just back off on that cell a degree or two. 6 degrees is too much.

[gmtech16450yz]

Try this dashpage, it might help if you see what's happening in this view...

(It didn't want to let me post a .vdp file, change the extension back to .vdp and it should work)

[harascho]

gmtech16450yz, you are a good teacher with your input I am able to proceed.. step by step.

I was playing with the shift points and TCC apply / release rpm's to get the big KR values at the low rpm side smaller.

Here are some logs I did with the modified settings. I also started to retard the high octan table in the area were the KR is still a little high, but I think I will be close or below the original settings to reduce the KR enough ???


Harald

[gmtech16450yz]

gmtech16450yz, you are a good teacher with your input I am able to proceed

Thanks for the compliment, I try. Every tech that's worked next to me for the last 25 years has thanked me for all they've learned from me so I must be doing something right!

Try this in your high octane table... (from the settings you had when you did that last log)
In the 1200 rpm row, reduce cells .20 through .40 by 3 degrees.
In the 1400 rpm row, reduce cells .20 through .48 by 3 degrees.
In the 1600 rpm row, reduce cells .32 through .56 by 4 degrees, except for cell .36, reduce that one by 5 degrees.
In the 1800 rpm row, reduce cells .44 and .48 by 3 degrees, and .52 and .56 by 2 degrees.
In the 2000 rpm row, reduce cells .52 and .56 by 2 degrees, and .60 by 4 degrees.
In 2200 reduce .60 by 2 degrees.

Get it?

BTW, your timing/ KR map is not reading properly, do you have the map column as "APCYL_DMA"? Did that dashpage I posted work for you? When you look at it in that view you can really see what's happening with the KR, lots of jagged blue lines that look like mountains are not good! That octane scaler line should stay pretty flat too.

Hope that helps.

[harascho]

Correct, for some strange reason my timing map doesn't read correct. In the charts of my dashpage B I can see the APCYL_DMA reading values up to 0.56 with KR present but in the timing map the max for it is 0.12...

I post my dashpages A and B under a different file extension, just rename it to .vdp
I also made a screenshot of the spark42 log where I see the KR values and the octan scaler rising.
I will try your settings later, first I have to get the timing map to read correct.

Harald

[harascho]

I got the map problem solved. Something went wrong when I copied the labels from the spark table. Now the readings in the map (timing_2) and the values in the dash B correspond. I was following the wrong track and adjusted the timing in the wrong cells. I will start all over from a original high octan table and start with +8deg throughout the whole table.. make some logs and reduce then in the correct cells.
Ha, getting smarter every day. I like this very much.. you have some progress every day and it's a fun to get used to it.

Harald

[harascho]

here are some more logs including a autobahn run and a log with the o2 sensor voltages. I am still looking for some extra mpg.

The only things I did so far is adjusting the TCC lock /release rpms, the up- and downshifts and I advanced the high octan spark table by +8deg.

After some test drives I retarded the high octan map in the cells where KR was present in my KR . So far I get a little better mpg, but mainly because I tweaked the AFM settings a bit to keep it engaged a a little longer..
what I can see from the fuel trims is that big variation of the long term fuel trims from -12,5% to +8% and the short term fuel trims from -16% to +15% within my last testdrives. For my feeling that's a lot. Does anybody have any ideas / comments?


Harald