Here we go. 1999 LQ4 6.0l/4l80e into 57 Chev

This will most likely be a running thread as things are tuned, tweaked, reverted and hopefully not explosive....

Engine Specs -

1999 LQ4 6.0L
- Stock internals (rebuilt)
- 243 heads
- BTR LS3 Stage 1 cam
- 221/228 duration @ .50
- .608 intake .571 exhaust
- 112+2 seperation
- Stock 2010 Camaro SS Manifolds
- Stock truck intake

4l80e was rebuilt.
P01 ecm

Currently we have the engine starting and idling on the stand with the attached tune/log.

I am new to tuning, so looking for any general advice, any glaring errors in the base tune. Once the engine is installed and I have more logs, changes, tweaks, I will post along in this thread.

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Injectors, larger ones will be 100% required for this setup. The stock 25lb/hr injectors are barely large enough for the 6.0, add the mods you have and you'll go way past 90-100% duty cycle in no time.

I suggest either some 31lb/hr injectors or even factory flex fuel injectors from a few years newer truck. The trucks in the 2002-2007 range came with 33lb/hr injectors from the factory. Any of these two will be plug and play data, grab a stock file from a 8.1 truck for the 31lb/hr or a flex fuel truck for the 33lb/hr, copy the data in.

Make sure fuel pressure is steady at 58psi when the engine gets installed.

This computer also allows for a speed density upgrade that I would suggest using. Even if you plan to never run boost, the upgrade is worth it because you will remove the secondary VE table that is a extra step and pain to tune. The upgraded OS will remove the table and leave you with just the primary table like all the 2001+ operating system run. Makes speed density tuning much faster and the MAF sensor will function like normal even with the upgrade.

We knew going in that the injectors may be a bottleneck. I am hunting for a set of the flex fuel injectors, hopefully I can track a set down with out breaking the bank even more!

How would I go about finding an upgrade for the OS? Does that incur more credits?

Click the OS tab, all the upgrades to the OS are in there.

OS upgrades are free. Just be sure to follow the prompts and always save your stock file in case you need to revert back to stock for some reason. OS changes also require a write entire and NOT a calibration only write.

To see all tables and options you need to be in advanced view under the edit tab.

Perfect, thanks.

Ran into other issues with the install so its been a bit.

Anyway, I did the OS upgrade but the secondary table is still there. I have a feeling I updated to the wrong OS.

I take it I should use the Speed density update and not the 1 Bar MAF?

so when you choose an OS for RTT 1 bar you can choose between SD and MAF. in both cases the maf can still be used.
the difference becomes which tables are allowed to have the RTT function. If you choose maf the MAF tables are allowed RTT. if you choose SD then the VE tables are allowed RTT.
the maf might not be useful down low around idle because of the cam but once airflow increases...say 2500 rpm and above then it may be useful to you.

most of us in here recommend staring with the SD tuning because its the default fueling. If you want to test the maf sensor out then you can activate it after you are done SD tuning. Use the MAF RTT OS with the tune settings from your SD RTT Files to quickly bring the error of the maf sensor down. play with the threshold for the maf to see what rpm works best for your application. usually the cam becomes an issue so you can test with the maf enabled at idle and if you start having issues you can raise the threshold up until those issues that appeared, go away again.
monitor the maf hz during wot and make sure you are not getting close to exceeding the maf axis. if you do then you can disable it and run full SD without any issues. With your setup, using the maf is up to you, the tuner, and whether or not you get close to the max axis values of the maf sensor calibration.

I did say in my first post to use the speed density upgrade. :)

Quote:

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Originally Posted by 5FDP

I did say in my first post to use the speed density upgrade. :)

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Yup you did, but when I was reading the notes I thought it did away with the MAF, so I went with the 1 Bar MAF that said it would do away with the secondary table, oh well, simple fix.

And thanks for the explanation, any info helps.

Its finally driveable! Had some brake issues and a small trans cooler leak to sort out.

All I have done here is take the running tune we had, installed the speed density OS and went for a drive. See lots of numbers telling me things are all over the place, but its a start.
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you should pull a lot of fuel out of the whole thing, not sure if you knew that or not. Also instead of commanding like a 11.6 in power enrichment you could go for more of a 12.3 or so is still on the safe side. Also your getting a bunch of knock retard. Your real rich and you don't have much timing at all so I'm sure you just need to desensitize the knock sensors.

Quote:

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Originally Posted by ryan_axberg

you should pull a lot of fuel out of the whole thing, not sure if you knew that or not. Also instead of commanding like a 11.6 in power enrichment you could go for more of a 12.3 or so is still on the safe side. Also your getting a bunch of knock retard. Your real rich and you don't have much timing at all so I'm sure you just need to desensitize the knock sensors.

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I did not. I think we threw a bunch of fuel at it to get it started in the first place. As for the knock, that may be gas related, still on gas from the old engine, going to drain it and fill with some 91.

No tuning here, just added better gas. This was just a short trip to a local cruise. Aboout how long is a good time for decent logging? 10 minutes? 20 kilometers?

Need to get my graphs and stuff setup. Having issues getting the af err setup as I have the pro and the wideband output only gives me volts. Is there something I am missing?


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Histogram cell count > 1000 is usually what I go by.

Perfect thanks.

Went for a bit longer run after a couple tweaks. Then blew a power steering line. At least I got some logs!

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Started speed density tuning today. So far things are okay. Found out quick to pay attention to what you are copy/pasting into the tables! Went from really rich to really lean pretty quick.

Only issue I am having is it does not want to slow down. I let off the gas and it sits around 1500 to 1800 rpm.

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Pretty cool once you get to tuning how quick it can go. Still getting some knock retard, but the timing table is starting to get cleaned up.

Found at least one of the issues on the slow down. Throttle cracker was out of whack right at the "in town" speed section.

You can just zero out the throttle cracker in the top left corner up to where you are having an issue. I will say there are at least 2 other ways to fix this too. One being fueling, the other being spark. Start with the cracker though, easiest to fix, and isn't all that important really.

thanks, using your youtube vids to tune, which btw are outstanding