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Help Needed with stft Bank 1 Wandering off and overall tune

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Im a little over my head here, trying to find stuff within the lessons and courses but Im just chasing my tail at this point and need assistance or guidance please.

LT4 Corvette, put AFR 195cc heads, Lunati 231/239 110sep cam, 24x TorqueHead Conversion, CAI, Long Tubes, No Cats, Full Exhaust.

Attached is the tune Im working on and a log file for HP Tuners, Any input is much appreciated, Thanks In Advance.

Attached Files

I've just had a quick look at your log file and it's apparent that there's very little activity from the O2 sensors (looking at the mv output from each bank O2). This can be a problem at idle with long tube headers as the O2 sensors don't get hot enough to operate correctly.

Where are you at with the calibration on this? Have you gone through and used a wideband to optimise your MAF and SD tables? A common solution to the issue is to run the PCM in open loop mode so that it ignores the O2 sensors completely. Of course this means your tune needs to be on point and also means there's no feedback to correct the inevitable errors that will creep in based on ambient conditions etc. Alternatively you can use a wideband controller to simulate the narrowband input to the PCM. There's some more reading on the problem here: https://forum.hptuners.com/showthread.php?7610-Oxygen-Sensors-*lazy-at-idle*-02s-EGT-long-tube-headers-closed-loop

Currently I don't have a wide band available, was trying to err on fuel trims to calibrate MAF and that's about as far as I've made it really cause things didn't seem quite right.

Ok, shop ordered in some new WB sensors (others had died on me) and I messed with the Idle range of the MAF and VE and "guesstimated" the entire range accordingly .. I still have strange stft numbers while adjusting these and you see on the log the idle is decent and then drops.. it doesnt stall but almost. also startup is a little hard and requires throttle when warm. Any help or direction is much appreciated, not sure if im able to attempt steady state driving or not, please let me know your best advise on that thanks again.

Attached Files

It looks like you've applied an SD patch yet you're still using the MAF? Is there a reason for this? Personally my preference is to use SD for a large cam but that's not to say you can't use the MAF. I can't see what you're doing on the throttle but if you're blipping the throttle then it's possible the MAF is undergoing some reversion and reporting a higher MAF frequency. The good news is that your O2 sensors are following the wideband pretty much and the trims are responding as they should. I'd personally fail the MAF and tune in SD.

Ok, Yeah, I was just following the steps in your course Video For HP Tuners and MAF and VE Scaling,

Here Are my most Recent attempts and in Steady State it seems a good bit better, but still having some issues with Startup and Idle, and of course since I am road Tuning, I gave up on MAF and VE for now, as any stop needed kept me overly busy on the throttle and clutch to avoid a stall and I need to address that before I do much more road tuning to finalize, any advise or quick links on that and Tuning SD completely (Im not as familiar with that, haven't seen too much in your courses with HP tuners for that ?) I greatly appreciate your help and what you guys are doing for Us.

In that attached Tune I reverted everything back out of SD and logged a test drive..... the Vehicle Speed isnt showing up on the Speedo either, but I did get the TPS working as well as some other things... however those config files are not in the zip this time, I will add them tomorrow. Thanks Again.

Attached Files

Follow the steps in the 1 Bar SD worked example and this will show you how to calibrate the VE table if you've applied the SD patch.

With a large cam you're going to need to increase the idle target (which it appears you've done), but also you'll need to calibrate the base running airflow tables. It looks like you've already made some changes here too but I don't have a base cal from your PCM so it's hard to say. The way i do this is to set up a histogram with the same break points as your base running airflow table and log the airflow into this histogram. Start the car from cold and allow it to come up to operating temp while scanning to fill the histogram. Once you've done that, copy and paste your histogram back into the base running airflow table.

Ok, I did attempt the BAF as you explained, Maybe it needs another go at that.., I will check in on the SD example. Thanks again

Ok here is the SD worked tune for this Vette and I must say I like this method of tuning much more, I have most everything sorted pretty well I think, if you dont mind have a look and see what you think. I am struggling with Hot Start Extended Crank and I am on my way now to drive with all the CL/PE/DFCO/STFT's and such re-enabled to see if the STFT's behave this time around or not. Thanks Again

This tune file is the result of making the adjustments from the log inside this file, so my aim was about -.5% from the errors seen in this log file, I will post new ones here shortly.

Attached Files

Tune with Re-enabled CL/STFT/PE etc... per the videos you mentioned above

Attached Files

Log of CL enabled tune above

Attached Files

It looks like for the most part everything is pretty close, except you've got some weird separation in the trims going on in overrun. It's a little hard to tell exactly since you don't have TPS logged. You've still got DFCO disabled in the calibration though. If you're having starting issues you may need to address the VE table in the cranking and initial startup areas, or potentially the cranking VE table.

I've also shifted this thread into the reflash forum as it's more relevant there.

Ok sounds good, however I am a bit confused as I was logging TPS, and I don't see where DFCO is disabled ? ?

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