View Single Post
      11-12-2012, 10:16 AM   #6491
MikeS300
New Member
 
Drives: 2010 335i xdrive
Join Date: Jun 2012
Location: Blacklick, OH

Posts: 18
iTrader: (0)

Lean AFR on Spool

If I could change the subject for a moment, I would like to talk about a lean condition on spooling. I looked around different forums and this has been discussed as a phenomenon related to some different types of tunes. I could not find much related to Cobb.

So I'm running Stage 1 Aggressive on 93 octane that has been tweaked by me to avoid boost overshoots. When I have been doing my WOT runs I usually start around 2000 rpm and go for it. I am set to use the spool fuel tables up to 3000 rpm like most of us. I noticed that my actual load can get in the high 100s during spool and that my AFR will go as high as about 16.1 and then it will start dropping after I get out of spool mode and hit about 12.2 in the higher RPM range.

Is this condition during spool where I hit 15 to low 16s AFR a reason for concern? I am working with someone at Cobb who is having me go into ATR and at the highest loads (in the Fuel (spool) table) up to 3500 rpm I am dropping the requested AFR by about 0.5 to 0.4 to try to richen things up a bit. Attached is a log from yesterday that shows what I'm talking about. I even logged fuel mode to show that my high AFRs happen in fuel mode "20", or spool mode. Any advice is appreciated. I need to do some more runs with my AFR richened up in the spool table if you guys think it is necessary to richen things up.
Attached Files
File Type: txt datalog1.csv.txt (17.4 KB, 36 views)
MikeS300 is offline  
0
Reply With Quote