Welcome to the North American Subaru Impreza Owners Club Saturday August 30, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 05-02-2005, 05:03 PM   #1
MINO
Scooby Specialist
 
Member#: 12841
Join Date: Nov 2001
Chapter/Region: SCIC
Location: jchattdesign.com
Default Logging AFRs by cylinder:

I would like to log my AFRs by individual cylinders but the LM-1 states that the O2 should be placed post turbo for accuracy.

Has anyone tried to get readings pre-turbo and more specificly by cylinder?
What were your results.

Thanks.
* Registered users of the site do not see these ads.
MINO is offline   Reply With Quote
Old 05-02-2005, 06:07 PM   #2
hippy
Scooby Specialist
 
Member#: 36528
Join Date: May 2003
Location: florida
Vehicle:
2002 Impreza Wrx
Silver

Default

A lot of the time the egt's are too hot before the turbo for the o2 sensor to opperate normally which is why the o2 sensor is supposed to be places after the turbo. It would probably be much less expensive to get a 4 way egt gauge and install an egt probe in each exhaust runner. If one is running hotter then another, you know that's the one ya need to add fuel to even if the a/f ratio is the same to start out.

peace
hippy is offline   Reply With Quote
Old 05-02-2005, 06:37 PM   #3
hondaeater69
Scooby Guru
 
Member#: 60324
Join Date: Apr 2004
Location: a pillow.
Default

THere's a thread around here where a vendor (SMC) logged EGT's by cyclinder. He was going to do AFR's next but i don't think he ever got around to it. You can do four way AFR's, not sure I'd keep them in there permanently due to the temps, but they'll be fine short term. Remember there's an 02 sensor at the end of your manifold. If you log that sensor with a WB post turbo, you will get identical readings down to 11.25 (which is as low as the front stock 02 sensor goes down to). That sensor is in ALL of our cars, and will last a LONG time. If I had to choose between four way AFR's and four way EGT's, i would choose AFR's all day long.
hondaeater69 is offline   Reply With Quote
Old 05-02-2005, 06:39 PM   #4
mavrick
Scooby Newbie
 
Member#: 78477
Join Date: Dec 2004
Location: Under the hood...
Vehicle:
04 Element block
Hydra pwrd t67

Default

Quote:
Originally Posted by hippy
If one is running hotter then another, you know that's the one ya need to add fuel to even if the a/f ratio is the same to start out.

peace
mabey I am reading it wrong but how would you just add fuel to ONLY 1 cyl.
Mav
mavrick is offline   Reply With Quote
Old 05-02-2005, 06:52 PM   #5
Jon [in CT]
*** Banned ***
 
Member#: 2992
Join Date: Nov 2000
Chapter/Region: NESIC
Location: Connecticut, USA
Vehicle:
02 WRX Sedan
Silver

Default

The problem with wideband sensors pre-turbo was exhaust back pressure, at least with NTK wideband sensors. This is/was according to Garfield Willis, who passed away last year. His websites are dead now, too, but here's what he used to say, thanks to the Way Back Machine: http://web.archive.org/web/200310291...ield/index.htm. Check out the Products>EGORmedusa.
Jon [in CT] is offline   Reply With Quote
Old 05-02-2005, 06:53 PM   #6
hondaeater69
Scooby Guru
 
Member#: 60324
Join Date: Apr 2004
Location: a pillow.
Default

/\/\ it's called standalone EM
hondaeater69 is offline   Reply With Quote
Old 05-02-2005, 08:29 PM   #7
mavrick
Scooby Newbie
 
Member#: 78477
Join Date: Dec 2004
Location: Under the hood...
Vehicle:
04 Element block
Hydra pwrd t67

Default

I was thinking that just checking I didn't think Utec was being used
mavrick is offline   Reply With Quote
Old 05-02-2005, 08:39 PM   #8
hippy
Scooby Specialist
 
Member#: 36528
Join Date: May 2003
Location: florida
Vehicle:
2002 Impreza Wrx
Silver

Default

Quote:
Originally Posted by Jon [in CT]
The problem with wideband sensors pre-turbo was exhaust back pressure, at least with NTK wideband sensors. This is/was according to Garfield Willis, who passed away last year. His websites are dead now, too, but here's what he used to say, thanks to the Way Back Machine: http://web.archive.org/web/200310291...ield/index.htm. Check out the Products>EGORmedusa.
Bosche wbo2 sensors have a built in heater circuit of some type which heats something in the sensor upto something like 1250F. If the exhaust gasses going though/past the sensor are hotter then 1250F, the sensor won't work accurately. This is why people put the sensor after the turbo. The exhaust gas temps after the turbo are cooler then b4 the turbo. Course everything I know is wrong, so beleive what you like.

peace

Last edited by hippy; 05-02-2005 at 09:19 PM.
hippy is offline   Reply With Quote
Old 05-03-2005, 03:15 AM   #9
bboy
Scooby Specialist
 
Member#: 56468
Join Date: Mar 2004
Chapter/Region: NWIC
Location: Seattle, WA
Vehicle:
04 Improved STI
Dirty White

Default

I've got 4 EGT probes. That's the best you can do. The O2 sensor can't handle the heat. I've never posted my data. I'll do that soon. Basically, the differences vary across the RPM range so you can't really tune to keep consistant EGT at all load sites, but you can adjust the individual injectors for WOT EGT variation so that the "peak" EGT can be normalized. With a Hydra EMS from Element Tuning you can make individual adjustments, and also other stand alones, not so sure it's possible with EM systems.

BTW you'd be amazed at the difference in EGT between exhaust port and the up-pipe with headers. It's like 200-300 C cooler and my header are coated inside and out.
bboy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Stage 2 log. AFR occilation and slow boost? Brock31 Open Source Reflashes 12 10-06-2009 12:18 AM
'06 Stage 2 WRX, logged AFR not matching map targets wage0052 Open Source Reflashes 27 01-16-2008 06:43 PM
Target Log for AFR over RPM range plus plus plus UTEC 3 04-22-2007 07:38 PM
afr logs carl s. Engine Management & Tuning 8 01-02-2007 10:49 AM
Logging with EcuExplorer and AFR? bmw50021 AccessPort 3 10-17-2006 07:52 PM


All times are GMT -4. The time now is 10:52 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.