well the TQ Management was part of the problem. She scoots now however the fuel was still rich and now I have some knock retard 
CK5
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Well at least it’s going in the right direction
Thank you everyone for the guidance and feedback.
I’m still a little shocked that Howell sent me two PCM’s with those TQ Management settings.
I’m still a little shocked that Howell sent me two PCM’s with those TQ Management settings.
Same, that really is disturbing. If I remember tomorrow I’ll take my laptop to work and compare those to a 5.3 6.0 and a duramax tune to see where it lands.
Nice work dude! I was starting to think you were going to have to carb swap it
Check my pulse if you see me put a carb on anything lol
Nice to see progress being made. Your last plot isn't showing any retard, but I would still up the Max Torque vs. RPM at least to stock levels. The numbers Howell has are lower than the published torque curve for the engine. Is there some part of the drivetrain they are intentionally trying to baby? The Max torque ECT table maxing at 80% is also really bizarre, but theoretically doesn't effect the timing. Although your plot above shows it's way overcalculating torque, which makes the retard you had at such low levels make more sense now, but maybe also means the Max Torque vs RPM isn't really doing anything.
The table you posted:
The 2003 table I posted:
The table you posted:
The 2003 table I posted:
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Keep in mind they've removed your low octane timing settings, such that it's technically setup for better than baseline gas. You can verify that it's real by temporarily upping the octane, but it probably is real, as it has a lot of timing. A little bit of knock retard sometimes is considered normal, but you're not even at WOT here, so it's definitely something to keep an eye on as possibly needing adjustment. It's hard to relate the kPa to airmass, but the table does have another 10 degrees to pull.well the TQ Management was part of the problem. She scoots now however the fuel was still rich and now I have some knock retard
So the question remains, why is it pig rich? Upping the fuel pressure has made things worse in that respect, but it's good to see the sensors tracking to adjustments. Your last plot is so rich for the first 6 seconds that fuel trims are maxed negative and the O2s are still pegged high.
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I do believe it is the same tune, they loaded the same into two different PCMs. Also suggests PCM 1 is probably good
Here's a very simple idea. Could the file still contain the flow rate for 6.0L injectors? 6.0 are set to 25.2 and 8.1L are set to 29.9. These are basically the lb/hr ratings. I mean, based on what we've already seen, there could be any number of errors in there.
Couple things to note.
1) I made all the changes that @Tnsejed noted a page back to the torque management settings. Not just the 350 bump to 640.
2) @Blue85 you mentioned that you didn’t see knock retard but I see it noted in two places at 4.2 on the screenshot from last night. Maybe I’m looking at the wrong figure?
3) The engine wasn’t fully warmed up therefore I believe the richness figures may not be a fair comparison to other screenshots provided. It’s never mattered if it was hot or cold, it would still rollover albeit a bit worse when it’s warm.
4) I haven’t spoke with Howell about the torque management settings but I will. I wasted a bunch of cash fixing something they should have figured out by now. And I likely have more adjustments to go.
1) I made all the changes that @Tnsejed noted a page back to the torque management settings. Not just the 350 bump to 640.
2) @Blue85 you mentioned that you didn’t see knock retard but I see it noted in two places at 4.2 on the screenshot from last night. Maybe I’m looking at the wrong figure?
3) The engine wasn’t fully warmed up therefore I believe the richness figures may not be a fair comparison to other screenshots provided. It’s never mattered if it was hot or cold, it would still rollover albeit a bit worse when it’s warm.
4) I haven’t spoke with Howell about the torque management settings but I will. I wasted a bunch of cash fixing something they should have figured out by now. And I likely have more adjustments to go.
If you have those runs from yesterday in a data log, send them over to Todd so he can look at them on his computer rather than trying to look at them on here from the screenshot. Us old guys can’t see that shit.
Is there a local tuner there that does LS work? Or even a remote tuner you’ve heard of. At this point I’d want a pro looking at it instead of guessing just to get my baseline right.
That’s still an option however I don’t know of anyone personally. I also have Larry’s tune that I need to look at it and compare to mine.
It is worth noting, most tuners do not like messing with the torque management stuff. And almost all cases, they might make some slight modifications to it, but they want to leave it in place. And there are a lot of good reasons to run it rather than completely delete it.
I think there are some strong clues here, as the PCM is overcalculating the torque while running very rich, which implies it's calculating airflow too high.
OK, it makes more sense knowing you already changed those tables.
I see the 5 degrees of knock retard. I was just saying you don't have torque management retard anymore.
I don't know anything about these factory swap type setups so please forgive my ignorance. I'm just wondering about the timing. On the aftermarket efi setups you lock the timing and then verify it with the timing light. Is that not something you can or need to do on a setup like this?
I was thinking this can tell if something isn't set right.
I was thinking this can tell if something isn't set right.
Screenshot logs aren't always the best. And Mark is way older than I am, even if his statement is true.
With that said I like some TM. On my rig I use transmission torque management as well as abuse mode. Slamming reverse during a climb or limiting power during front and rear digs was something I wanted. You don't have that option but that's ok.
I'm glad to see the fuel pressure corrected. So when you pull the vacuum its right at spec correct?
I won't touch a tune where the vehicle has any fuel, air, or spark mechanical issue. You're just chasing your tail and there's a good possibility when it gets fixed you made shit worse.
Two more question: Firstly don't worry about Howell. Leave them alone for now. The whole cooler heads will prevail thing. Have you looked and found that was stock GM TM tables in that tune? This could be a clue.
Second: I didn't read much so I don't know this whole backstory. Per our PM, have you checked the injector part numbers that are in the engine. if so what are those?
Those are the first questions that need answered.
Exactly. My last post is getting at this. Everyone is posting as I was typing. I'm working and typing and getting interrupted while typing at the same time. lol. I'm not there yet in saying the airflow model is incorrect. We don't know what is incorrect, if anything.
True but they can probably see something better than we can on the other side of a laptop and could identify some other gotchas. Like I said, just someone to baseline the tune and then adjust from there.
Also, any reason he can't just upload a base 8.1 tune and go from there? I'm ignorant on the LS swap stuff honestly so I'm just offering some thoughts.
