Injection Timing Assistance Requested

[jsllc]

Like it Scott - Like it a lot

Didn't even know it was possible to have the graphs SOI wrap around... The one graph on the table page needs to be 6 cells smaller height wise, but I can take care of that easy enough later on...

Think this one is very very close to the final if there's any way to add the makeup rpm and make it to where you can just copy and paste the rpm tables right out of the tunes?

Very nice...

I can do this. Does anyone KNOW the math on MAKEUP RPM or NORMAL RPM for sure. What do they do beyond 4096? We should not guess here. Better to leave them off and ZERO out then to add in bad math.

[jsllc]

Like it Scott - Like it a lot

Didn't even know it was possible to have the graphs SOI wrap around... The one graph on the table page needs to be 6 cells smaller height wise, but I can take care of that easy enough later on...

Think this one is very very close to the final if there's any way to add the makeup rpm and make it to where you can just copy and paste the rpm tables right out of the tunes?

Very nice...

Here is a aversion that you can paste in NORMAL RPM.

[jsllc]

I made an attempt to implement the guidance offered in the spreadsheet but don't think the results were positive (the car is requiring more fuel at all rpms to reach stoich). Anyone care to take a look at what I have implemented and make suggestions?

The car is an 07 CTS V with and EForce blower, LSA heads, Pat G cam, headers, and currently implementing dual widebands (so the logs don't show the AFR/Lambda data). The attached excel file is what I have implemented. The log file represents the results. Fuel trims were primarily neutral before implementing the EOIT adjustments. I realize that it has been discussed that the VE and MAF will have to be retuned to implement the schemas recommended here but wouldn't the trend be for the fuel trims tend to be more negative if the combustion is more efficient? BTW I did add some timing hoping that the new EOIT would hold the advance but no such luck so ignore the knock.

I did not write the notes. Just worked on the math. I do not believe they are correct.
- Above 2500 rpm or so, try to get SOIT just before PPV
- Above 4000 rpm or so, get EOIT-FRC 20-30 degrees before IVC

For example on my car if you attempt the 2500rpm recommendation you will have fuel being injected AFTER IVC. I believe they should read

- Below 1536 rpms or so, try to get SOIT-FRC just after EVC
- Above 3000 rpm or so, try to keep EOIT just before IVO PEAK
- Above 4500 rpm or so, keep EOIT-FRC at least 20-30 degrees before IVC

[GHuggins]

I made an attempt to implement the guidance offered in the spreadsheet but don't think the results were positive (the car is requiring more fuel at all rpms to reach stoich). Anyone care to take a look at what I have implemented and make suggestions?

The car is an 07 CTS V with and EForce blower, LSA heads, Pat G cam, headers, and currently implementing dual widebands (so the logs don't show the AFR/Lambda data). The attached excel file is what I have implemented. The log file represents the results. Fuel trims were primarily neutral before implementing the EOIT adjustments. I realize that it has been discussed that the VE and MAF will have to be retuned to implement the schemas recommended here but wouldn't the trend be for the fuel trims tend to be more negative if the combustion is more efficient? BTW I did add some timing hoping that the new EOIT would hold the advance but no such luck so ignore the knock.

Your injectors are apparently pretty big or your pulse widths are wrong? Your way too retarded for the injectors - this is one of those "catch 22's" if you will Big injectors and small pulse widths = target more on closed intake valve...

[jsllc]

I made an attempt to implement the guidance offered in the spreadsheet but don't think the results were positive (the car is requiring more fuel at all rpms to reach stoich). Anyone care to take a look at what I have implemented and make suggestions?

The car is an 07 CTS V with and EForce blower, LSA heads, Pat G cam, headers, and currently implementing dual widebands (so the logs don't show the AFR/Lambda data). The attached excel file is what I have implemented. The log file represents the results. Fuel trims were primarily neutral before implementing the EOIT adjustments. I realize that it has been discussed that the VE and MAF will have to be retuned to implement the schemas recommended here but wouldn't the trend be for the fuel trims tend to be more negative if the combustion is more efficient? BTW I did add some timing hoping that the new EOIT would hold the advance but no such luck so ignore the knock.

Sorry I know better, depending on when you flashed the car, if you adjusted the injector pulse width adder for injector tip temp and where you tuned the MAF/VVE your FTrims will not be a indicator of anything. Many things in play.

[sssnake]

You don't have any of your pulse width adders accounted for in the spreadsheet it seems, so the graphs won't be correct.

I went back and added them in. They are so small I would consider them in the noise for everything but maybe around idle.

How large are the injectors?
What is max Boost?

Deka shorty 63lbs FI114962
8 lbs (most are seeing nearly 10lbs of boost with my pulley on the LS2. To date I have considered this a good thing - better flow - but who knows)

The fuel system has been upgraded to a manifold referenced PWM returnless system with a BAP. BAP kicks in at 1 Bar/100KPa.

Yeah I know the PWs are a little different but the trend is pretty solid. I have seen large differences in PW at different times in logs even with decent trims. I ASSumed it was because of the manifold referenced fuel system. I will go back and set up a histogram to get better averages and see if that helps.

Thanks all!

[GHuggins]

Couple things I noticed when playing with this Scott - First off the injector pulse width cells below 2400 rpms are protected even though they shouldn't be and then even though the regular chart shows the injection timing "soi" coming back around before the 720 degree mark - the black graphs don't correspond simply because the rpms on them don't go high enough? I know realistically most LS engines won't see anything above 7000 rpms, but is it possible to add a couple more black charts Please and Thank You


I'm also attaching a demonstration sheet of a cam and blower setup running 16psi I know is working very well even though I honestly know the injection timing could be a touch more advanced by redline... This is solely pulse width information during a dyno pull which will include transients, so honestly you might want to just look above 2500 rpms for this reason...

[GHuggins]

^^^ I also didn't enter in the cam specs, but you get the idea

[Atomic]

Im jealous of all the parameters you have to play with in the Gen4 computers. I still mainly do Gen3 stuff and there isnt squat for injector timing control there, relatively.

[sssnake]

OK - I have asked this question in another thread but this seems to be the home for definitive EOIT timing discussion so I will ask here as well. We want to use the injector pulsewidths from a WOT pull NOT cruising correct (I had forgotten that little gem earlier). From the post GHuggins referenced on page one the pulsewidth values should come from a dyno pull or WOT run. I will be updating my data shortly. I would think to get your best highway fuel econ you would want to put your cruise values so that you maximize econ if your vehicle is a daily driver. Just a thought. Mine ends up not being hugelydifferent either way.

[07GTS]

just noticed on the latest v14 all my calculations are now out, have traced it to the makeup adder and i think it was calculated as 30 deg delayed in the spreadsheet (soit dosnt change but eoit does) where it should be 30 deg more advanced like the rpm and ect adders do (soit should advance when makeup deg increased and eoit stay same) if someone can check this also unless im mistaken..?

[J-CUE]

Wait!
So you're saying that makeup advances SOIT, and not EOIT?
I thought makeup was another adder to the normal EOIT to advance it away from the boundary to make room for makeup?

[07GTS]

yea i was under the impression it was an adder to before the boundary like the ect and rpm tables are they both advance before boundary, going on my cam specs and fuel out exhaust it works out that way to my calcs and actual fueling changes, but if i have got it wrong then i need to make some changes in my eoit targets

[GHuggins]

Y'all are right - makeup is moving the graphs in the wrong direction - should be advancing, not retarding... Not sure if Scott has had a chance to look at any of this or not? I know the pulsewidth settings aren't working right below 2500 rpms either and I think it might be nice to have one more black rpm graph at 7100 and then have the big graphs show line detail for the main soi and eoi lines? I found that helped with seeing things while playing with numbers on the inputs page...

On a side note - everyone should enter in some stock ls3 or other engine settings - they target ppv for 1000 and less rpms and then move to a closed intake valve with rpms... They also have the ability to inject fuel with the intake valve closing, but still open... Never bothered to really look at it before having these graphs...

[scottt28]

Y'all are right - makeup is moving the graphs in the wrong direction - should be advancing, not retarding... Not sure if Scott has had a chance to look at any of this or not? I know the pulsewidth settings aren't working right below 2500 rpms either and I think it might be nice to have one more black rpm graph at 7100 and then have the big graphs show line detail for the main soi and eoi lines? I found that helped with seeing things while playing with numbers on the inputs page...

On a side note - everyone should enter in some stock ls3 or other engine settings - they target ppv for 1000 and less rpms and then move to a closed intake valve with rpms... They also have the ability to inject fuel with the intake valve closing, but still open... Never bothered to really look at it before having these graphs...

I daytrade and the stock market has been my focus. Will try to revisit this soon

[Higgs Boson]

I daytrade and the stock market has been my focus. Will try to revisit this soon

you should be killing it right now.

[scottt28]

you should be killing it right now.

Yes, I am absolutely killing it.

Version 15 attached. It includes three more graphs which takes it out to 8192 rpm. Not sure who protected stuff, but I removed the protection.

Are there other issues? What other mods are needed?

[jsllc]

This should fix EOIT and PW adder. As before the protection has no password so remove if you want. All of this assumes it works as described. Otherwise it is useless.

[GHuggins]

This should fix EOIT and PW adder. As before the protection has no password so remove if you want. All of this assumes it works as described. Otherwise it is useless.

PW in MS - 2500 is the last editable cell then it "autoanimates" from there down - is there a reason? Seems like it does something weird if you remove the protection and modify?

[jsllc]

PW in MS - 2500 is the last editable cell then it "autoanimates" from there down - is there a reason? Seems like it does something weird if you remove the protection and modify?

Okay, got it. Simple fix.