Author Topic: gammae readings  (Read 8201 times)

Offline Seight-v8

  • Sr. Member
  • ****
  • Posts: 339
  • BHP: 6
    • Members Page - Scott Richmond
gammae readings
« on: December 29, 2009, 05:37:10 pm »
hello all,

finally getting to do some plyaing/tuning with my engine.

Lambda has been running at about 0.7-0.80 so i've adjusted the req fuel down for now to get it to read better.

When i've looked at the vemslogs....gammae is reading 130% all the time.

What alters this reading....is it the vetable????.

And do i need to get this to 100% when the engine is warm?

cheers

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline gunni

  • Hero Member
  • *****
  • Posts: 1492
  • BHP: 37
Re: gammae readings
« Reply #1 on: December 29, 2009, 11:20:42 pm »
Look in your logs.

Or view the other enrichment gauges,
what program are you using?

Offline Seight-v8

  • Sr. Member
  • ****
  • Posts: 339
  • BHP: 6
    • Members Page - Scott Richmond
Re: gammae readings
« Reply #2 on: December 30, 2009, 01:08:51 am »
still trying to understand what the the logging means.

Not sure what the best method of getting the correct lambda values are.....dont understand why the reading are not what the lambda table shows yet.

Dont even know if my VEtable readings are doubled like the manual says it should be....

tried halving the req fuel, but wouldnt even start....

cheers

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline dnb

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 837
  • BHP: 19
Re: gammae readings
« Reply #3 on: December 30, 2009, 02:47:08 am »
Gammae does not appear to read right for me either in recent logging, despite everything appearing to be right with the fuelling.  I have a feeling that it might not be used in the most recent firmwares, but I haven't got to the bottom of all the changes for 1.1.62 to 64 yet.

(1.1.64 is a good firmware as far as I'm concerned)

Leaving aside the sensor readings (which should be fairly obvious) here's roughly what the gamma parameters do:

Gego is the % change applied by the closed loop lambda parameter - eg 95 is 5% fuel removed and 105 is 5% added.

Gair is the % change applied by air temperature - set with the air temperature vs throttle lookup table.

Gwarm is the % adjustment applied during warmup.  Set with the warmup and afterstart parameters

Gbaro doesn't seem to do a lot.  It's for barometric correction, but this should be turned off on a NA engine.  In my firmware it's stationary at 128 (half scale) and this has shown to be acceptable.

I think Gammae is the combination of Gego, Gair, Gwarm and Gbaro.  It latches to somewhere around 100 when the RPM is zero, so don't worry if it looks "wrong" when the engine is running.

Gve is the % adjustment set in the VE table.  This will appear to be double what it should be if you have halved reqfuel and doubled the VE table contents to get some more resolution. 

Offline dnb

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 837
  • BHP: 19
Re: gammae readings
« Reply #4 on: December 30, 2009, 03:44:13 am »
Send me your last working config and some logging done using that config and I can probably point you in the right direction.

Offline Seight-v8

  • Sr. Member
  • ****
  • Posts: 339
  • BHP: 6
    • Members Page - Scott Richmond
Re: gammae readings
« Reply #5 on: December 30, 2009, 04:49:59 am »
cheers dave,

just sent them as of 22:40pm tonight...so let me know if nothing arrives.

I'd love to get out and drive this thing....but still covered in 3ins of ice here....so its gotta wait.

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline dnb

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 837
  • BHP: 19
Re: gammae readings
« Reply #6 on: December 30, 2009, 05:57:01 am »
Looks like I have some files.  I'll have a think and email back some changes.

Hopefully the ice will go away soon enough.  I'm missing the dry weather myself now.  I don't mind cold too much - the TVR is good at heating! 

Offline Riff

  • Jr. Member
  • **
  • Posts: 35
  • BHP: 0
Re: gammae readings
« Reply #7 on: February 22, 2010, 04:48:43 pm »
Just wondering, why should baro correction be turned of on a NA engine?