Everything there is to know about MegaTune Auto-Tune

MiseryQ · Post by **MiseryQ** » Mon Sep 12, 2005 3:07 pm

619 and the "lumpy factor" works very good. Smoothed the map considerably. Also adjusted my VE in a few areas I apparently did'nt tune well.

Unfortunately it's not making anymore relvent changes to the VE, going back and forth 1-2% )':
Guess I'm finished tuning for awhile (:

I'll edit in a before and after VE when I get ScreenShot installed on my notebook.

Post by **efahl** » Mon Sep 12, 2005 6:20 pm

whittlebeast wrote:Last night I was messing with Extra 025v2 and MT 619 I was not getting the option to Autotune

Andy,

Make sure the "allowAutoTune" is inside the [AutoTune] block, it was moved from the [TableEditor] to be with all the auto-tune stuff (see the long post above with the full ini block in it).

Eric

bazzer · Post by **bazzer** » Mon Sep 12, 2005 11:39 pm

Hi all

Is the "EGO Switch Point" redundant when using AFR target tables ? surely the switch point will change with different points in the AFR target table.

Or do I have this all wrong ?

I quick pointer to setting up O2 correction for use with the auto tune feature with extra 024s9 would be great !!!

Cheers

Bazzer

neilb · Post by **neilb** » Tue Sep 13, 2005 12:16 am

Would it be possible to put some guildline setting on for using this for ego correction, accel, decel enrichment, what should be turned off or on etc.

Thanks

Neil

Post by **efahl** » Tue Sep 13, 2005 7:44 am

bazzer wrote:Is the "EGO Switch Point" redundant when using AFR target tables ? surely the switch point will change with different points in the AFR target table.

That sounds right to me, but I'm not sure how the target AFR tables are used, so we might be completely wrong with this.

Bazzer and Neil,

I don't really have a good handle on the EGO correction parameters, but my gut feel is that you want to limit things and slow them down so that the auto-tune doesn't overshoot. So, I'd suggest something like:

Ignition events: 2 to 6 * number of cylinders
Authority: 10-15%
Step size: 1%

Pick the ignition events based upon the volume of gasses between the valves and sensor, larger volumes and higher exhaust back pressures should have a higher value to account for the latency of the gasses as they pass through the system (you don't want to be correcting something until you're sure you see its effect).

For MT's [AutoTune] settings, I'd make sure the window (x- and yLimit values) are such that you aren't going to tune outside a reasonable RPM and MAP range initially, open it up later if you feel things are working out well.

Eric

Post by **efahl** » Tue Sep 13, 2005 7:46 am

Oops, forgot about the AE and all that. I don't think you need to worry about any other settings, as the EGO control algorithms all appear to turn off correction (i.e., set the correction factor to 100%) whenever AE, decel, warmup or any number of other enrichment types come active. The 100% EGO value in turn has the effect of turning off the auto-tune.

Eric

Post by **efahl** » Tue Sep 13, 2005 10:18 am

MiseryQ wrote:Guess I'm finished tuning for awhile (:

Oh, no, you don't get off that easily... Go back and mangle the table manually, then re-autotune and see if it gets back to where it is now.

dbubb · Post by **dbubb** » Tue Sep 13, 2005 1:19 pm

I've looked around several places, but have not been able to find out if v619 will work with MSnS Extra firmware 024s11 (or at least that's what it says at the top of the MT screen even though I can't seem to find this firmware release anywhere!)
Any help is appreciated.
Dan

MiseryQ · Post by **MiseryQ** » Tue Sep 13, 2005 3:18 pm

efahl wrote:Oh, no, you don't get off that easily... Go back and mangle the table manually, then re-autotune and see if it gets back to where it is now.

OK I'm bored and to broke to finish my V3 board ): $10K wedding this weekend, so... I'll do it (:

I'll generate a table with MegaTune from my DD2K3 estimates, which'll be really far off.
I'll have to make MegaAutoTune very aggressive or it won't be drivable and set my egoCorr to something very high.

MiseryQ · Post by **MiseryQ** » Tue Sep 13, 2005 8:58 pm

I made my settings aggresive and went for a drive with a generated VE table.

Code: Select all

[AutoTune]
	table = veTableMap ; Should be the map3d_id of a TableEditor entry.
      allowAutoTune 			=	on
      corrector				    =	egoCorrection
      xRadius 				    =	800				; rpm (probably)
      yRadius				    =   5				; map (probably)
      xLimits				     =	600, 6000		; rpm (probably)
      yLimits			        	=   25,   100		; map (probably)
      initialStartupInterval	          =	0.5
      updateInterval			  =	0.5 			; seconds
      proportionalGain			 =	0.5
      lumpiness					=	5				; percent

The settings are the same as RV8Tunes' aggressive settings.
Decel leaning became a big problem. It shot straight past the lumpiness setting.
There was one bin with 28% difference and another that was similar but I did'nt get to look at before it changed.
This did'nt just happen in the lower bins but also at 35KPA.
My idea about the cause of decel leaning was wrong.

I'll try again tomorrow night, this time making proportionalGain a setting that will keep changes below the lumpiness setting.