Author Topic: Tune by Statistics - VemsTune  (Read 49212 times)

Offline multiplex

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Tune by Statistics - VemsTune
« on: April 06, 2010, 08:59:48 am »
seems like a great feature, i'm just not sure if its generate realistic numbers?

in the old days i would use MLV to tune my map and re-import into vems.

with vemstune, that doesn't work all that well

any tips on using tune by statisics? or is there still work to be done
« Last Edit: December 02, 2010, 05:00:59 pm by mattias »

Offline gunni

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Re: tune by statistics - vemstune
« Reply #1 on: April 06, 2010, 02:00:21 pm »
I´ve tested it from a log. Looked to make the right adjustments.

Just give it a go and see if it comes up with sensible numbers.

Offline MWfire

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Re: tune by statistics - vemstune
« Reply #2 on: April 06, 2010, 03:20:41 pm »
seems like a great feature, i'm just not sure if its generate realistic numbers?

in the old days i would use MLV to tune my map and re-import into vems.

with vemstune, that doesn't work all that well

any tips on using tune by statisics? or is there still work to be done

for me works very good if rpms/kpa dots are set good.

Offline GintsK

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Re: tune by statistics - vemstune
« Reply #3 on: April 06, 2010, 04:37:57 pm »
for me works very good if rpms/kpa dots are set good.
What you mean with dots?

Do you used MLV before for analyze? How it compares?

Offline MWfire

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Re: tune by statistics - vemstune
« Reply #4 on: April 06, 2010, 04:46:19 pm »
for me works very good if rpms/kpa dots are set good.
What you mean with dots?

Do you used MLV before for analyze? How it compares?
I used mlv, and vemstune is better.
My engine has 180Nm at 2000rpm, 168Nm at 2200rpm, 183Nm at 2400rpm. So if i put rpm dots 2000 2400 tune by statistics doesn't work well, but i i put rpms dots 2000 2200 and 2400(because engine here has some resonance) tune by statistics works great.

Offline GintsK

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Re: tune by statistics - vemstune
« Reply #5 on: April 06, 2010, 04:58:30 pm »
Clear! I will try it shortly! :)

One feature I miss since MSTweeks3000 times: this software allowed plot datalog in colored plot. So it was possible to determine optimal places for rpm bins/dots very easy...

Offline dnb

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Re: tune by statistics - vemstune
« Reply #6 on: April 06, 2010, 06:07:45 pm »
What you mean with dots?

He means the "first differential of" (RPM or MAP) or "change of"

Not had much success with this myself, but that is a lot to do with the crazy cam I have - the statistics don't know which samples to bin.  My own stats tuning engine is broadly similar but I have (by necessity) had to put a lot of effort in to throwing away the samples where horrible things were happening...  This means I get better results.

Offline GintsK

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Re: tune by statistics - vemstune
« Reply #7 on: April 06, 2010, 09:57:55 pm »
dnb, how you compare results of both: MLV and VT analyser?
« Last Edit: April 06, 2010, 10:52:41 pm by GintsK »

Offline dnb

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Re: tune by statistics - vemstune
« Reply #8 on: April 07, 2010, 03:54:03 am »
I haven't used MLV, only the VT analyser vs my own analyser.  (Obviously mine is better, but I'm biassed and it's been heavily optimised for big cammed v8 engines...)

Offline MWfire

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Re: tune by statistics - vemstune
« Reply #9 on: April 07, 2010, 04:04:52 am »
I did my map with vemstune, maximum error is 2% :). But i have data from 300km trip for tuning.

Offline mattias

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Re: tune by statistics - vemstune
« Reply #10 on: April 07, 2010, 06:53:13 am »
I datalogged to the internal SD card and downloaded 2x90 mins log of me driving 250 km and optimized my cruising VE bins to hold +/- 1% close to target, worked very well.

Be sure to have rpm and pressure bins where the engine spends the bulk of the time. This means that you keep an eye on the rpm at which you hold certain legal road speeds, 70-90-110 km/h are normal here in Sweden. Those rpm bins will then be very easy to optimize since the data will hit those bins very often.

Don't make changes to bins where you have a small number of datalogged points and where the data suggests large correction, this is usually due to engine break (fuel cut) or acceleration enrichment.

Offline GintsK

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Re: tune by statistics - vemstune
« Reply #11 on: April 07, 2010, 12:55:18 pm »
Does analyser filter out records after unstable situations like acceleration enrichment?

Offline qwkswede

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Re: tune by statistics - vemstune
« Reply #12 on: April 15, 2010, 11:29:06 pm »
I'm not clear which log file and VE map gets used for this analysis tool. For the VE map, I just open a saved config file. But for the log file that matches that config, how do you choose it? There seems to be no option on the VE Tune by statistics page. Is it just the newest one?
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Offline mattias

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Re: tune by statistics - vemstune
« Reply #13 on: April 16, 2010, 09:45:27 am »
A log file saved with VemsTune contains the configfile and therefore the VE map is known, so the analysis will suggest alterations to that VE map. The log also contains configuration changes, I'm not sure if/how that is taken into account when the analysis is made. My point being, don't make any changes to your VE or lambda target map while datalogging if you wish to do analysis later. Do it in steps. Datalog, analysis, apply changes, .. etc.

The SD card logs do NOT contain the config, so you need to load a save config of the one used when the SD card log was made if you want to do any analysis and alter your VE map. VemsTune makes a point out of this when you open a SD card log.

As with other things in VemsTune this is a moving target, bear that in mind and suggest stuff and ask away if the function is not clear or needs enhancements.

Offline qwkswede

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Re: tune by statistics - vemstune
« Reply #14 on: April 16, 2010, 11:23:31 am »
Thanks. I'm off to do some datalogging and tuning then.
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