MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: Janner_Sy on November 15, 2010, 06:01:37 pm

Title: convert lambda to AFR
Post by: Janner_Sy on November 15, 2010, 06:01:37 pm: guys what the fasctor you multiply the lambda readings by to get your AFR?

i have 14 in my head for some reason!!

cheers
sy
Title: Re: convert lambda to AFR
Post by: Hedge on November 15, 2010, 07:49:06 pm: If you use the search you find this.

http://www.mk5golfgti.co.uk/forum/index.php/topic,121.msg123381.html#msg123381

:P
Title: Re: convert lambda to AFR
Post by: damoegan on November 15, 2010, 08:01:13 pm: 14.7 :smiley:
Title: Re: convert lambda to AFR
Post by: PDT on November 15, 2010, 09:04:09 pm: AFR is a far more precise factor as it has a higher resolution than Lambda.
Title: Re: convert lambda to AFR
Post by: Janner_Sy on November 15, 2010, 09:33:26 pm: in your opinion, what do you reckon is the optimum AFR for the TFSI?
Title: Re: convert lambda to AFR
Post by: Poppa Dom on November 15, 2010, 10:41:47 pm: Good question - have often wondered this myself - depends on the atmospheric conditions on the day, but I reckon 12.1-12.2?
Title: Re: convert lambda to AFR
Post by: PDT on November 16, 2010, 08:39:34 am: Quote from: Janner_Sy on November 15, 2010, 09:33:26 pm
in your opinion, what do you reckon is the optimum AFR for the TFSI?

Under what type of conditions? Cruise, light throttle, idle, WOT, etc.... Ideally around 14.4 at cruise/ idle and 11.5-12 under load, also look at exhaust gas temps as well as AFR.
Title: Re: convert lambda to AFR
Post by: bacillus on November 16, 2010, 03:59:02 pm: I was led to believe just under 12 at top rpm was ideal.
Title: Re: convert lambda to AFR
Post by: Janner_Sy on November 16, 2010, 04:43:57 pm: Quote from: PDT on November 16, 2010, 08:39:34 am
Quote from: Janner_Sy on November 15, 2010, 09:33:26 pm
in your opinion, what do you reckon is the optimum AFR for the TFSI?

Under what type of conditions? Cruise, light throttle, idle, WOT, etc.... Ideally around 14.4 at cruise/ idle and 11.5-12 under load, also look at exhaust gas temps as well as AFR.

on a dyno for example where it is ran at WOT for the ful RPM.

Whats the threshold where it makes safest peak power/torque for example a track day, and then a lower safer setting for daily usage?
Title: Re: convert lambda to AFR
Post by: PDT on November 16, 2010, 05:15:55 pm: Theres no real rule to follow, some engines will make more power at a leaner mixture than others, its not an exact science. A naturally aspirated engine can sometimes make more power at 13afr but the leaner you go, the hotter the egt's get and can cause you to retard the ignition timing slightly, which in turn can lose you the power you gained by leaning the mixture, its all about trial and error and testing.
Title: Re: convert lambda to AFR
Post by: Janner_Sy on November 16, 2010, 05:40:15 pm: in regards to the TFSI then?

what do you aim for in your ed30, if yu were to give it agressive settings for a track day?
Title: Re: convert lambda to AFR
Post by: PDT on November 16, 2010, 10:11:18 pm: If i was mapping a tfsi I would aim for around 11.5afr and then keeping a close watch on the egt's. If egt's get high then i would richen the mixture a touch and retest.
Title: Re: convert lambda to AFR
Post by: Cupra R on November 17, 2010, 04:47:52 pm: are you guy's logging MB 031 for a Lambda reading then multiplying it by 14.7 to get AFR?
Title: Re: convert lambda to AFR
Post by: Janner_Sy on November 17, 2010, 05:42:40 pm: yes mate. it was the 14.7 factor i wasnt sure about
Title: Re: convert lambda to AFR
Post by: Cupra R on November 17, 2010, 06:05:41 pm: Quote from: Janner_Sy on November 17, 2010, 05:42:40 pm
yes mate. it was the 14.7 factor i wasnt sure about

:happy2: Thanks mate, I've been doing quite a few of these log's recently too and I just wondered if I were doing it correctly :signLOL: