First time tune and datalog advice LS2 C6

[Corvettechris86]

Finally got around to uploading my tune and a quick datalog of my 2007 ls2 6l80 corvette. I?m still learning daily about tuning and tweaking it. My ltft?s are a lil crazy at first because I just reset them but appear to be -2 at wot. The first two pulls i seen a decent amount of knock retard after resetting the ltft?s but after that I wasn?t seeing much of any wot on the other pulls. I would like to try to lower my shift time on the 1-2 shift a bit lower than im seeing of .25-.3sec, seems like I would have to lower the torque adder times but don?t want to make it too harsh. Not sure if my oncoming and offgoing pressures are high enough but the shifts in pattern Y are pretty firm. I uploaded the stock tune for a compare file if anyone can help. Any advice would be greatly appreciated and thanks in advance!

[Corvettechris86]

Well i went for a data logging cruise again tonight, 86 degree iat temps and i was getting 2 degrees knock retard, I don’t get why it?s getting kr tonight under better conditions and same fuel.

[LS ROB]

I'd say its your fueling. VVE and MAF both need to be tuned. Looking at the log, you are only logging a MAF channel but it really doesn't show any helpful data cause you need to log "MAF Sensor" as well. VVE looks untouched from the stock file. Add cylinder airmass, Volumetric Efficiency, and dynamic airflow to your channels.

**Edit.. Add Knock Learn Factor to your channels as well.

[dhoagland]

So you're using fuel trims to tune your WOT pulls?
Or am I missing something?

You cant do that.
Notice when you stomp on it you go into open loop (Fuel System Status... OL - Accel/... in your log channel) and your trims Zero and the o2 voltage is pegged high, which it should be as your richer than its normal narrow band range.
Using the fuel trims to create an error log is excellent at steady state or slow transitions without PE (power enrichment).

The only way to Tune open loop is with a Wideband, your knock could very well be from a lean condition

[Corvettechris86]

I appreciate the advice, I haven?t messed with the fueling at all because I don?t have a wideband yet. All i really did there was set the PE at 2000 rpms which I might need to bring back to stock 4000rpms? I?ve just added a degree of timing above like 4000rpms and been checking for knock. Watched the goat rope garage video on maf calibration tuning last night, looks like I need to do that. Thanks again everyone for the feedback and taking the time to look over my tune. I need to make sure my oncoming and offgoing pressures on the trans tunes are okay seeing im running 246psi line pressure. My part throttle shifts are faster than my wot shifts for some reason.

[dhoagland]

PE at 2000 RPM is fine..
I would leave it there until logging says to move it, having it early is a better than late option.

Be very careful with on comming and off going.
This can really make stuff very bad very quick.

I would reccomend getting familur with logging and tuning your engine long before tuning on the transmission.

[Alvin]

Well i went for a data logging cruise again tonight, 86 degree iat temps and i was getting 2 degrees knock retard, I don’t get why it?s getting kr tonight under better conditions and same fuel.

It will occasionally have knock. That is normal. If it doesn't show knock every once in a while than the sensors are bad or they are turned off.

It shouldn't be repeatable knock. Or knock you can reproduce.

[Corvettechris86]

Thanks guys, I only added 10% pressure to the oncoming and offgoing. I think the max psi i seen there was like 80psi but the line pressure is set to 246psi. Not sure if I have too much or too little oncoming/offgoing to meet the .13 1-2 shift time. Best ive seen was .25 on the 1-2 shift at 6700 rpms wot. As far as the knock, No I can?t replicate it and usually it?s not more than 2 degrees kr. When data logging and it says spark advance is that before or after the knock retard? Thanks again guys, I really want to learn everything I can on this platform.

[Alvin]

I don't recommend changing shift pressures on a 6lxx trans. Set shift desired times to something reasonable.. like 0.2 sec

[Corvettechris86]

I don't recommend changing shift pressures on a 6lxx trans. Set shift desired times to something reasonable.. like 0.2 sec

Should I zero out the torque adder and just set it to .2 sec and try? Right now the torque adder is still factory shift times so maybe that?s why I?m seeing a .25 sec shift at wot? Just under the impression it needed more pressure to complete the faster shift on time without slipping. I really need to calibrate my MAF after watching the goat rope garage video on how to do it. Looks pretty simple, just trying to do as much as I can without currently having a wideband. Not sure how accurate the torque output is and or if thats at the crank or transmission but it?s showing I went from 378 tq to 390tq with the minor tweaks in the tune I posted.

[Alvin]

the shift time should all add up to something between .2-.25. If you up the pressures, it might shift faster but it will try to learn back to it's commanded shift time.

I don't touch pressures on these hardly at all. FWIW.

Calculated torque is not accurate.