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496Stingray
May 26th, 2015, 02:11 PM
Curious if anyone can enlighten me. Is High Speed mode also the same as PE? See pic...

Also would raising the MAX MAP KPA beyond 105 allow the throttle to open farther? Curious not that it will increase power but may add noise on an NA engine.

Thanks in advance.

joecar
May 26th, 2015, 02:50 PM
B8024: going up above this RPM, enter into MAF-only mode (MAF is used exclusively).
B8025: going down below this RPM, re-enters into dynamic-air mode (MAF during steady state throttle/airflow, VE during transient throttle/airflow).

Regardless of PE.


BTW: you can disable VE by setting B8024 to say 400 rpm and B8025 to zero.

joecar
May 26th, 2015, 02:51 PM
Post your E78 tune file.

496Stingray
May 27th, 2015, 01:46 AM
One of the latest but I am pulling timing out at the .40 G/s range, this ones an experiment for best cruise mileage around 75-80@2000 RPM however I think I hit the wall of diminishing returns.

Added a log from this mornings run about town.
Around frame 3360 is where I leaned into it in 2nd gear with good load on the engine coming up a hill. KR as I expected it would since I intentinonally set the timing very high in that range to "find the knock limit" I am really surprised that it took 29 deg of timing to finally hit KR! :shock: Good cylinder heads, lower compression of the L96 vs the LS3 etc, I figured it would take a tad more timing to make peak power on 93 octane vs the LS2-LS3 which seem to do best around 23 deg but never thought it would handle that much timing. I think peak power will be at a lower #. The thing I am trying to deterimine now is why the timing is going that high. Some from Cam phasing B5154 but not that much At first glance I thought B5112 Fuel Mixture correction. But that doesnt make sense as my Lambda is on target and wouldnt add anywhere near that much timing.

My LM2 is being repaired it had a bad molex on the board but my fueling is around 12.7 AFR in that range. I logged it last week prior to the timing changes. I could probably richen it up a bit up top. Commanded is showing around 12.33 based on how I have PE currently configured but the wideband shows a tad leaner than that.

-Rob

496Stingray
May 27th, 2015, 05:07 AM
In the spirit of sharing....
I made changes to the timing tables and as expected it picked up power and eliminated the 1.5 deg of KR.

I have yet to run it above 5500 and likely wont as this 6L90 seems to already have some pump whine shreaking in protest over 5000 RPM.
40k on the odometer.
7200 lb truck.

Only thing bugging me is the throttle stopping at 83.9% even though the MAP is showing 93Kpa. Leads me to think something is limiting my torque command. Do you know what PID I might look at to see what is commanding it? Possible the trans is only allowing a max TQ per gear.... Ill keep digging.

-Rob

496Stingray
May 27th, 2015, 12:39 PM
My last bits of testing for the day with a different set of tweaks on the above tune.
I moved B8300 Torque Limiting MAP from 100 kPa to 110 just to see if it would allow more airflow into the engine.
The results dont lie.... My WOT @5600 went from 93 kPa to 97 so were inching in the right direction. Not certian with a stock airbox and K&N panel if it can get much better than that?

cindy@efilive
May 27th, 2015, 01:42 PM
Rob, I've removed your .ctz files from your posts because they contain non-publicly available parameters. If your tune files were edited in publicly available software feel free to post them again.

Cheers
Cindy

496Stingray
May 28th, 2015, 02:20 AM
Rob, I've removed your .ctz files from your posts because they contain non-publicly available parameters. If your tune files were edited in publicly available software feel free to post them again.

Cheers
Cindy

Yikes I completely forgot about that. Thanks, :)