5.3L with LS3 cam tunning? LTFT 20-30% to lean

[04colyZQ8]

I'm new to the hole Gen IV tuning program, I did a Ve, and maf tune on a E40, using a wideband, to populate the VE table. Never tuned for much of a cam before.

I have a 2007 5.3L LH6 from a 07 Silverado crew cab, all aluminum block DOD motor with 243 heads. would have been a E38 PCM originally. 2580681 is the gm part number for my injectors. I had to switch to a E67 to run the motor in my 04 Colorado. I'm using a 07 CTS-v base tune (E67 PCM). I installed a LS3 cam, LS7 lifters, LS3 valley cover deleted my dod. I'm running a LS2 intake with the 2580681 stock 07 truck injectors using spacers, and I'm running the 07 truck 88mm TB, Volant cold air intake, with LS7 maf (E40 style maf was used on the CTS-v originally). Using OBX try Y 09 Colorado 5.3L headers, high flow cats.

Cam specs 0.551/0.525 204/211 117 LSA Should be 21 HG at idle, and around 400 HP @ 6100 RPM, and 395 ft/lbs @4900 rpm

I have changed the IAT axis to match the LS7 maf/IAT, and copied the MAF freq data from a 09 Colorado file to ge the correct LS7 maf info. The injectors I've copied from a 07 trailblazer that uses 2580681 injectors. I've changed the displacement from 6.0L to 5.3L

Now I will definitely need a MAF, and Ve tune, at the very least, but I thought with a mild cam like this my VE wouldn't be so far off? With the stock Ve table for the CTS-v I'm idling around 25 to 30% LTFT and setting to lean codes for both banks. I tired copying the 09 Colorado 5.3L VE, hopping that might be a closer start, I'm still almost exactly the same, and running far to lean! Its really hard to start, and wants to stall easy too! If I unplug the maf, IAT seems to stay at 32F which is close to what it is running at the temp in the shop anyway, then it starts way better and idles around -5 to -8% LTFT way better idling, what is this?

What's so far off here, my MAF or my VE? How can I get this idling well enough to start disabling the maf, and setting it up to run speed density so I can dial in my VE, using my wideband?

Can I just add 20-30% to my VE across the board to get a half decant idle? Is there any good GEN IV how too, I don't see any, like there was for the LS1, and E40s

[5FDP]

Adding 20-30% to the VVE would make it insanely rich, that's not how you'd want to tune it.

You can use the built in LTFT + STFT data logging graph to help you bring the trims back in check. There is a write up in the VCM scanner section about it. Or just create a graph/chart with a wideband for tuning the VVE. Make sure you are making changes to both the manifold switch open and closed tables, then calculate coeifficents.

Even though the cam isn't large you still changed the airflow of the engine, small cams can still toss everything out of adjustment with ease. The air intake and different MAF sensor add to it being off.

You can choose to do the MAF first or the VVE first, both will take equal amounts of tuning.

[04colyZQ8]

I just copied and pasted as much of the 5.3L envoy tune as I could except the Dod, and throttle settings, as I don't want to trip PO606. I'm hoping this will give a little bit of a closer start. My original motor from the Silverado was a direct interchange the 07 5.3L envoy, I didn't want to copy the tune from the E38, to the E67, but 07 E67, to 07 E67, should hopefully give me some kind of idle, that I can start tuning with, go to be a better start then a 6.0L LS2.

I don't see any specific guides for the E67? If I follow the instructions for the E40 putting it into SD mode the same for the E67? Will that work, and do I use the same histogram for generating the Ve table of the E40? Or is there ones setup for the E67? So little info for the E67, that I can find?? Then I'll have to copy paste by percent fro the generated Ve, into the virtual Ve and generate the coefficients?

[04colyZQ8]

I for one cannot find a single histogram in version 3 so confused with version 3!! and the histograms for version 2.24 do not have a E67, guess I'll try a E38 2bar? or E40 histogram?

[schpenxel]

Quit posting that. It's called graphs in V3, and I posted the link in another thread that walks through creating them.

[04colyZQ8]

http://www.hptuners.com/forum/showth...d=1#post469508

See my rant here! Then if everyone's gonna make me feel like a idiot someone for love of.. Update the gen iv e67 stickys to reflect the new program then?? It still talks about histograms and blue cat virtual ve program links for it are gone btw!!

[5FDP]

It's understandable that you may not know how to use it well right off the bat but the update has been out for like over half a year or something like that. I don't tune for a living either but I did take a few weeks of reading and understanding the new setup before I even tuned with it, then once I did it was like nothing much changed.

Putting the vehicle into speed density is the same. Set all 3 MAF dtc's to fail on first error, set the MAF fail high hz to 2hz, low fail to 1hz and that's it. Remove the MAF channels while scanning to prevent it from skewing data and you are good to go.

[04colyZQ8]

Ok, thanks I'll give that a whirl, what about disabling DAFCO, and LTFT, and setting up the commanded EQ, and AFR ratios? Plus removing the yellow MAF wire, seems to me that's what I did on the E40? And sorry for sounding like a dick, you know I've worked on this project for a year off on, and a lot in the last three months creating a custom OS in raw hex to get cruise working. Then when cruise finally works, and I'm ready to put a tune in this thing to get it to run, I thought that would be the easy part since I've done that in the past, but no totally new program to learn, like I'm starting from scratch again. I just wasn't mentally prepped for that, Oh well huge learning curve for me!

[5FDP]

Disabling some settings can depend on the route you take. If you wish to use your wideband to tune the VVE/MAF you can disable the short term and long term fuel trims. Or you can use the fuel trims with the LTFT + STFT graph.

Go ahead and disable the DFCO and COT to just rule those out, it's a good peace of mind thing.

No need to remove any wires from the MAF, you can do it all from the editor like I said above. Do those settings and it should revert straight to speed density.

[04colyZQ8]

Disabling some settings can depend on the route you take. If you wish to use your wideband to tune the VVE/MAF you can disable the short term and long term fuel trims. Or you can use the fuel trims with the LTFT + STFT graph.

Go ahead and disable the DFCO and COT to just rule those out, it's a good peace of mind thing.

No need to remove any wires from the MAF, you can do it all from the editor like I said above. Do those settings and it should revert straight to speed density.

Ok, thanks I found a you tube video on getting my wideband through the a/c port. So I will likely disable LTFT+STFT if I can get it working

[Jon S.]

If this is your first time working with a Gen 4 ECM (E38 and E67 are tuned using the same techniques), or your first time tuning a Gen 4 with a cam swap, then this process will test your patience and cause frustration.

Everyone will have their own way of doing things, but I will suggest 3 things that may get you going a little more smoothly.

Read the "Rich After Flash" phenomena thread - the injector adder table is likely already set to zero if you are using a truck tune, but double check to make certain.

Tune the MAF curve first - setup the tune to run in MAF only mode, beginning at 400 RPMs. You may need to revisit the MAF curve after tuning the VVE, but if you do, the touchup will likely be minor.

Use your the EFILive scanner to create the BEN factor for the MAF retune. I see from your posts that you have transitioned from EFI to HPT. HPT is great software, but is very different from EFI. This approach will limit the amount you need to learn (i.e. the amount of frustration) to get the MAF curve close enough for now.

Everyone appreciates the cutting edge software updates that HPT consistently implements, but keeping up with the changes to the scanner can be a real PITA.

[04colyZQ8]

If this is your first time working with a Gen 4 ECM (E38 and E67 are tuned using the same techniques), or your first time tuning a Gen 4 with a cam swap, then this process will test your patience and cause frustration.

Everyone will have their own way of doing things, but I will suggest 3 things that may get you going a little more smoothly.

Read the "Rich After Flash" phenomena thread - the injector adder table is likely already set to zero if you are using a truck tune, but double check to make certain.

Tune the MAF curve first - setup the tune to run in MAF only mode, beginning at 400 RPMs. You may need to revisit the MAF curve after tuning the VVE, but if you do, the touchup will likely be minor.

Use your the EFILive scanner to create the BEN factor for the MAF retune. I see from your posts that you have transitioned from EFI to HPT. HPT is great software, but is very different from EFI. This approach will limit the amount you need to learn (i.e. the amount of frustration) to get the MAF curve close enough for now.

Everyone appreciates the cutting edge software updates that HPT consistently implements, but keeping up with the changes to the scanner can be a real PITA.

Well I actually have two controllers both with the same custom os I designed, one licensed to efi, one licensed to hpt, I own both efi, and hpt. I useually just create custom os, or remove vats or setup injectors ect for poeple to beable to driveva block to a tuner.

But since this rides my own and I have the software I thought I'd give it a try, tune it myself.
I've only tubed ounce in my life few years ago, with a e40 and hpt, wideband afx ntk through ac port.

Now I love efi, because I can make custom files. But never tuned with it, before and there doesn't seem to be a way to run a wide band through efi at the ac port. At this point it may be faster to rewire my wide band to my efi interface directly has inputs. And learn that software tunning curve.

Hpt I'm more used to using, then efi but that's 2.24 hpt, v3 is a new ball game!


I only have one minor complaint about efi it writes slower then hpt, at least it seems that way? But I think I'm done with hpt for the time being, might as well use efi?
Sounds like you have both? Which do you think I should use? I'm open to using a combination of both as well

[schpenxel]

Use your the EFILive scanner to create the BEN factor for the MAF retune. I see from your posts that you have transitioned from EFI to HPT. HPT is great software, but is very different from EFI. This approach will limit the amount you need to learn (i.e. the amount of frustration) to get the MAF curve close enough for now.

Maybe I'm having a blond moment. What is "BEN factor"?

[Jon S.]

Maybe I'm having a blond moment. What is "BEN factor"?

No blonde moment, you just don't have any experience with EFI.

[Jon S.]

Well I actually have two controllers both with the same custom os I designed, one licensed to efi, one licensed to hpt, I own both efi, and hpt. I useually just create custom os, or remove vats or setup injectors ect for poeple to beable to driveva block to a tuner.

But since this rides my own and I have the software I thought I'd give it a try, tune it myself.
I've only tubed ounce in my life few years ago, with a e40 and hpt, wideband afx ntk through ac port.

Now I love efi, because I can make custom files. But never tuned with it, before and there doesn't seem to be a way to run a wide band through efi at the ac port. At this point it may be faster to rewire my wide band to my efi interface directly has inputs. And learn that software tunning curve.

Hpt I'm more used to using, then efi but that's 2.24 hpt, v3 is a new ball game!


I only have one minor complaint about efi it writes slower then hpt, at least it seems that way? But I think I'm done with hpt for the time being, might as well use efi?
Sounds like you have both? Which do you think I should use? I'm open to using a combination of both as well

HPT supports far more platforms, and has many more parameters than EFI. I would suggest that moving forward, you transition to HPT, but there will be much to learn. To get your own vehicle drivable, you could use either, or both in combination.

It sounds like you purchased the base version of the HPT hardware (not the Pro version, which has available inputs to integrate a wide band oxygen sensor). The Pro version is really the best option for a serious tuner.

[schpenxel]

No blonde moment, you just don't have any experience with EFI.

Gotcha. Yeah I googled it real quick and got a lot of posts on EFI's forum so figured it must be something with their setup. I have no real experience with it so that explains that.

[Jon S.]

Sorry Schpenxel .... doing too many things at once.

In EFI speak BEN = Base Efficiency Number, or the correction factor (percent error, if you will) generated by logging wide band oxygen sensor data, while in open loop operation.

[schpenxel]

Ah ok, makes sense