LLY tuning help

[Dashman]

Hello,

I am hoping that someone(s) may take a look at my scan and tune, and offer some advice. I am looking to build 3 tunes for my truck, a mileage tune, a performance tune, and a tow tune. First, I would like to build the performance tune along the lines of 500 hp and 800 ft-lbs. I am having trouble understanding the injection timing. The scan shows the main timing starting before the pilot timing, and I don't understand why. Is 0 degrees related to TDC after exhaust, prior to intake? Also, is the air under compression prior to injection? I guess the bigger question I have is, when in the stroke is the injection taking place? Also, according to my scan I am showing negative boost, why? I uploaded the PIDs I thought would help me with editing. Thanks in advance for replies!

PS: I love this stuff!

[mecanicman]

upload your config file, seems to work fine for me. Not sure what your trying to accomplish with tune, seems kinda screwy to me, injection timing especially.

[Dashman]

Thanks for your response Mechanicman! I'm just trying to mess with this software and build a tune that I can learn from, so that when I add my upgrades I'll have a tune for power. I would also like to build another for economy and a third for towing. I did some research today and found out that diesels fuel in the powerstroke. What are the limits of injection BTDC and ATDC (-5 to 80)? Also, is a negative timing value indicating BTDC or ATDC. I'm trying to smooth out the stock tune, add some fuel, smooth out the timing, and add some boost. I created another tune this afternoon that's a lot smoother, but still has problems. This new tune has rattle and smoke, and it still doesn't want to get passed 3300 rpm. Check out this new one and let me know what you think. Thank you again for your time and effort!

[Dashman]

I'm gonna remove my previous attached files. For starters, I didn't get the responses I was hoping for. And lastly, the attached tune file was junk. I was over fueling when I should have been under fueling. I travel typically between 5000 and 7000 feet elevation, so these files weren't gonna help anyone trying to find a file to use. Also, I don't have the proper gauges to get a good feel for my tunes, except from test driving. No hard feelings, and maybe through private messaging next time.

[Dashman]

What is the most advanced injection timing anybody has used for the pilot, without any adverse effects? What is the affect of increasing the interval timing with respect to RPM? Why wouldn't you want to keep the interval timing fixed, and only increase the base timing with respect to RPM? Also, what is the most negative timing (ATDC) to end the main pulse width timing without creating smoke? Lastly, what causes the turbo chirping and whining? Could it be that I have the vanes closed too much at low RPM?

I hoping that the moderator of this forum will chime in with their expertise.

Thank you for your responses!

[Red Heeler]

I'm in the same boat as you, LLY tuning with HPT is very rare.

[jeepcj776]

just got a 05 lly and did some tuning. wish there was more tunes to compare it to thou

[elite_cyborg]

I have a lbz tune if you want to compare

[Dashman]

Attached is my latest tune. I tried to smooth out the stock tables, for fuel quantity, boost, pulse widths, and timing. I did adjust the torque management tables to help adjust the shift characteristics. I smoothed and reduced the vane position tables in an attempt to spool the turbo quicker, but it's only in the EGR off tables. I checked and adjusted the timing with a spreadsheet, and I created a scan configuration with histograms. I'll post that with my results of this tune later. I don't have any information on it because I don't have any aftermarket gauges on my truck. I've just been going off of feel and performance. Let me know what you think, and trade me your tune files so I can compare. Thanks!

Was taking forever to attach the file, lost my patience, I'll try it again later. Sorry.

Got it finally!

[Dashman]

Someone check this out, and give me some feedback. Is it useful? Where do I need to tweak my timing? Thanks!

[elite_cyborg]

here is my lbz tune for you to compare

[Dashman]

What's the deal with calibrating the MAF sensor air flow vs voltage? Is there any benefit? When I've logged mine, there is only a small percent difference at each voltage. How do you know what your intake can actually flow? How do you know when your intake is no longer providing the air that you need? How do you match fuel to the air or boost that you actually have?

[elite_cyborg]

I'm new to the diesel scene but usually you would log stft and ltft and plug in the values into the maf tab.

[Dashman]

When scanning, what is Calculated Load % used for? I would like to find a specific way to log torque with respect to shift points. I don't want to have to guess at the torque management fueling to get the shifts right. Any clues?

[mecanicman]

I believe you would be better logging delivered engine torque. I believe this what the pcm uses to for the torque management. The load percentage calculation is not used for tq management and scewed by changing the tune as far as I can see.

[Dashman]

My truck had an outdated Operating System, and I had no idea. Thanks to Mechanicman's post I start to realize that he had something that I didn't. My goal was to log fuel vs torque vs RPM, so I could edit the torque management tables accruately without having to guess, but I didn't have the PIDs that Mechanicman had. Thanks also to guys like Pat McSwain (McRat Racing) for posting the web site http://tis2web.service.gm.com/tis2web which helped me determine which operating system I needed. Also, a shout out to Bill Henn @ HPtuners for the advice. I ran away with a $53.40 bill from my Chevy dealer this afternoon, which was half the hourly rate. Guess I can't call it the Stealership, this time, LOL. I can't blame them. I'm so stoked! Now I can continue to play with this stuff, right on! Thank you all!

I'm getting a few DTCs that may be related to my Instrument Cluster. The oil pressure gauge is out, along with the speedometer being intermittent, and I'm not certain about the temperature gauge. I think I may be hooked into a used cluster as a stand in, while I repair mine (thanks to good posts on Duramax Diesels.com). Then it's, finish my custom 4" exhaust, and purchase a new Volant intake with scope for later this spring. YEEHAW!!!

[Dashman]

Can anyone figure out why the boost pressure would surpass the MAP? Check out the pic of the chart. Would this indicate that I have a high pressure leak in the CAC? Thanks for any feedback.

[Dashman]

Where did the tune repository go to? I haven't been able to find it.

[ajamesbond007]

I can still get to the tune repository... Also, if you have questions about economy, tow, and other fun tunes, let me know. While I mostly work with EFI live on diesels, its basically the same in HP, just a different interface. Email me at [email protected] if interested!