WOT timing - EB 3.5

[murfie]

DO you have a data log showing what your absolute load is doing at that time?

[metroplex]

Rock steady 1.6-1.8 airload.

[murfie]

On the stock tune the combustion stability limit is just above the stock peak boost. Have you tried modifing the tune so that boost is not increased but just doesnt drop off from the stock peak? Then adding timing and see where you can get with the stock 14-15 psi.

The way I would approach this would be to get control over boost with the wastegate as a proper turbo car is setup and not controlled by the throttle. Make sure the throttle is not closing and the wastegate is holding boost around 15 psi. This will give you less turbulent air for a better high load burn.

[metroplex]

The timing at WOT is the same whether the boost is either stock 9-11 psi or 14, 15, 16, 17, or 18 psi. My actual throttle is wide open when my pedal is WOT. Wastegate is steady. I can hold up to 18 psi to redline and during/after shifting as well. What I found was that the turbos don't really like it above 17 psi and they are just pumping heat at that point. I think I mentioned before my WOT timing with the factory stock tune is the same as the WOT timing with more boost.

[murfie]

https://www.google.ch/patents/US5893349

I wonder if there are some missing tables for setting the crank angle at peak pressure threshold as described in this patent.

[metroplex]

I don't see the relationship between that patent and the lack of timing adjustability.

[murfie]

I saw on car get stuck in a cold start spark table when getting on the throttle for unknown reasons. yours is getting stuck in base which is nearly the same thing. You are unable to increase spark and have a rich condition at the higher loads. If there are hidden PPCA tables that we can not see this would explain why your spark seems stuck and why you car is going rich. Those tables would lock both values to obtain what the ECU thinks should make peak cylinder pressure. I want to say this is related to the popcorn limit, but am not really sure. Maybe Eric can look into this and confirm.

For now I would make sure your Base fuel table is stock, and everything related to O2 sensor temperature control is right. You could even try lowering the CL O2 enable temperature to make sure it has no reason to use any thing related to cold or base tables.

You could also try flashing the stock tune back on with a full write and take a full read again just to eliminate any possibility of a corrupt tune file.

[metroplex]

It does this with the factory stock tune, 9-11* advance max.

The car isn't stuck on a cold start table, it isn't stuck in base either. It switches to base at WOT conditions, but cycles between the different tables in normal driving conditions. It's not in a rich condition either at higher loads. I'm not sure where you got that idea from. The airload could be 1.8 at 4500 RPM and my commanded lambda = actual lambda (not rich). It dips slightly richer (slightly, as in 0.82 vs 0.85) above 5800 RPM but I don't run it past 6000 RPM anyhow. I think the popcorn limit is only for 2015-up, because I've never seen it on my 2014.

Which EcoBoost engine have you tuned where you are able to increase final spark advance through your tune? I'd like to see what changes you made.

That said, I ran 12.6 with just my tune at one of the crappiest tracks in MI (no other hardware mods). I'm just trying to see if I can increase the spark by a few degrees to see if I can improve the tune a bit.

[murfie]

'Stuck' may be the wrong word, but the wrong OL spark source for WOT is what I meant. I'm pretty sure the stock 3.5L engines go to borderline spark source at WOT unless some other limit happens. They may go to base if you are using the lambda spark base tables to add spark which is common to do. This method works, but I wonder if its limited because of the ECU thinking the base spark source is like the cold start tables and it uses hidden tables, such as the ppca values described in that patent.

I know you are not using the lambda spark able to add spark. You are trying to use the BKT. Which makes me say the ECU is stuck on it.

For what its worth I have not heard of or seen an eco boost that spark advance was able to go much higher than stock if any at all. From what I gather ecoboost engines don't like much advance. Id like to see if these few degrees more are possible as well.

[metroplex]

I wish I had logged spark source with the stock tune. With the lambda I'm running, the lambda spark table isn't adding much spark, would I be able to just add spark to that table?

[posenheimer]

Timing increased.jpg


I added to all of the tables in green to achieve my desired timing For my Methanol injection

[murfie]

Timing increased.jpg


I added to all of the tables in green to achieve my desired timing For my Methanol injection

Does your spark source show 'base'?

[metroplex]

Posenheimer: I can play with BKT and MBT all day long without making a difference in the final spark advance. I've made changes to the other tables as well, but they didn't have an impact either. The only one I didn't play with was Lambda spark advance.

[posenheimer]

Does your spark source show 'base'?

Yes it sure does.

Timing2.jpg

[metroplex]

That looks like you're nearly WOT, and at 22* spark!

May I ask what you did to the tables you identified in green? You don't have to share your meth injection tune data, I'm just curious about the actual amount of spark added to each of those tables.

In BKT and MBT, did you increase all of the values at high load / high RPM by a certain amount over stock?
What did you do for Preignition and Cyl Press Limit ? Max them out to 63.5*?

For IPC Spark Max, the stock values were fairly high (30* or more, just like MBT) so what was changed?

Any input on Lambda Spark, did you just increase the values for your commanded lambda?

[posenheimer]

That looks like you're nearly WOT, and at 22* spark! My throttle pegs at 76.5 degrees at wide open throttle and pinches on the shifts only.

May I ask what you did to the tables you identified in green? You don't have to share your meth injection tune data, I'm just curious about the actual amount of spark added to each of those tables.
I have followed the path through the mapped points and have added to the stock tables quite a bit, the tranny/ turbo setup seems to peak spool at 4200 to 4400 depending on downshifting and gear the actual gear I am in, I am at over a mile high DA so i assume the turbos are a smidge lazier than lots of you lower and more fortunate guys with your good air. LOL.
IIRC if you punch it from a roll it starts in mapped point 4 I command 12.xx at 3500 in the last to load rows, and ramp it in to 15.xx degrees at 6000rpm in the borderline table, and follwed the mapped points as the rpms climb up. It is between 4 and 8 degrees higher than stock. Then I smoothed out all the borderline timing tables via raising low spots. I raised the MBT tables by the same amount over the stock values in all of the tables for the corresponding mapped points (I hope that makes sense)

In BKT and MBT, did you increase all of the values at high load / high RPM by a certain amount over stock?
What did you do for Preignition and Cyl Press Limit ? Max them out to 63.5*? Yes I did changed those whole tables to 63.5

For IPC Spark Max, the stock values were fairly high (30* or more, just like MBT) so what was changed? I just smoothed it by raising the low points to be smoother basically, so not raised by alot really.

Any input on Lambda Spark, did you just increase the values for your commanded lambda?
I had 0 knock with straight water injection on those timing adjustments , keeping the IAT2s in check, as these turbos are really pushed hard in my tune now. I added washer fluid in stead of straight water, and added in the additional timing via the lambda adder table. About 3 to 5 degrees over whatever the stock values were, after I went with a 50/50 mixture. It took alottttttt more timing than I figured it would. I could see 5or 6 degrees more than stock typically on mpi cars I tune, but this is now like 8 to 11 everywhere. The richer, the more timing in this table, at all the leaner stuff .96 and leaner I left that stock. I am commanding .82 at peak torque and .83 up top, plus the methanol sprays when I am that high, so I am actually running a bit richer than that, the fuel trims cant yank the fuel fast enough, but it hasnt seemed to be an issue, its close to stock richness until about 5200.


I swear you are hitting some sort of a limiter, I never seemed to encounter the problems adding the timing after I tuned mine. (The Wifes car actually). I hope you can make heads or tails out of what I have tried to explain.


Sidenote: The SHO no longer adds in the timing automatically after I tuned it, I do not know why, or what I changed, or what limiter I might be hitting but it is always saying base as the spark source. I do not know what the spark source was in the stock tune.

[metroplex]

Traditionally with Fords, you just increased the BKT values to increase timing. MBT is usually never changed as that represents max brake torque for the engine assuming no detonation, but it should never get that high as BKT is the limiting factor. The ECU usually looks at both tables and picks the lowest, along with various adders. I don't see how IPC Max Spark is really used in the calculations, leaving Lambda Spark as the only table that would provide the added spark. But your last comment is interesting, are you saying the SHO no longer has the extra timing you commanded?

[posenheimer]

Traditionally with Fords, you just increased the BKT values to increase timing. MBT is usually never changed as that represents max brake torque for the engine assuming no detonation, but it should never get that high as BKT is the limiting factor. The ECU usually looks at both tables and picks the lowest, along with various adders. I don't see how IPC Max Spark is really used in the calculations, leaving Lambda Spark as the only table that would provide the added spark. But your last comment is interesting, are you saying the SHO no longer has the extra timing you commanded?

No, I am saying that the car used to "self advance" the timing, it would have negative values in the knock retard, but since I have been tuning on the thing, its always just zeroes. I know it pulls between the lower of the two tables betweet MBT and Borderline Knock, I dont know if I needed to add the timing to the MBT or not, so I just did, but all those values are much higher already than the borderline tables. It didnt seem to matter, so I left them.

[metroplex]

I think I figured it out. I did a few things, but the one I think that worked to change my spark source to Borderline at WOT was:

32396 Spark Retard for Combustion Effects RPM vs Load.
I zeroed out that table, and got that idea from the F-150 EcoBoost stock tunes in the repository.

I also made a few other changes after looking at the F-150, so these MAY be required as well, but they don't stand out to me as being solely responsible:

50227 Spark Low Load Max vs Time: I made the entire column 55
38060 Spark Cyl to Cyl #1: All 0
38065 Spark Cyl to Cyl #6: All 0
38053 Spark Cyl to Cyl Offset: Made all the -2's to -1's

Of course I also made Preignition and Cyl Pressure all 63.5, but that by itself did nothing.

This makes me wonder if the F-150 EB 3.5's all have their spark source show as Borderline while WOT.

[metroplex]

In Borderline Knock mode at WOT, it's trying for 15-17 degrees of advance versus the 6-11 degrees in "Base" mode.