Welcome to the North American Subaru Impreza Owners Club Wednesday August 20, 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 > AccessPort

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 08-05-2011, 10:41 PM   #1
RoninSTI
Scooby Specialist
 
Member#: 49278
Join Date: Nov 2003
Chapter/Region: NESIC
Location: New England
Vehicle:
11 STI
SWP

Default Help analyze log, 2011 STi Stage 1 OTS knock event

So I was hoping some of you guys that know what you're doing could take a look at this log and let me know if I have an issue or not.

Stock 2011 STi, 93 octane running the 93 octane COBB off the shelf stage 1 map. Temp approximate 70 degrees fahrenheit. 4th Gear pull

3300-4300 RPM the FKLC shows -1.4.

If there are any parameters i'm missing that can help out, let me know and i'll do another pull.

Thanks

https://spreadsheets.google.com/spre...dGMXc&hl=en_US
* Registered users of the site do not see these ads.
RoninSTI is offline   Reply With Quote
Old 08-06-2011, 08:13 AM   #2
xatnys
Scooby Newbie
 
Member#: 271829
Join Date: Jan 2011
Chapter/Region: RMIC
Vehicle:
2011 WRX STI 5-dr
WRB

Default

I'll preface by saying I'm by no means an expert. However, generally speaking you shouldn't see Feedback Knock at WOT under high load. However, your log shows a very low level of Fine Knock Learn. I don't see that as a problem. You're not going to come anywhere close to totally eliminating knock on these cars, especially with an OTS tune. Personally, I'd do a couple more 3rd and/or 4th gear pulls to redline and check for Feedback Knock at high load. Tip-in knock and or random, low, knock events at times are generally considered "acceptable." Also, make sure not to bog it. Going full throttle position at low RPM causes knock almost every time.
xatnys is offline   Reply With Quote
Old 08-06-2011, 10:33 AM   #3
RoninSTI
Scooby Specialist
 
Member#: 49278
Join Date: Nov 2003
Chapter/Region: NESIC
Location: New England
Vehicle:
11 STI
SWP

Default

Thanks for your input. I'm going to do a few more logs with rolling the throttle at the low rpm. I will do 3rd and 4th and see if it's repeatable.
RoninSTI is offline   Reply With Quote
Old 08-06-2011, 09:22 PM   #4
RoninSTI
Scooby Specialist
 
Member#: 49278
Join Date: Nov 2003
Chapter/Region: NESIC
Location: New England
Vehicle:
11 STI
SWP

Default

In case anyone else comes across this thread with the same issues, please read the following...

http://www.romraider.com/forum/topic5371.html

Section four describes what's going on better than I ever could. Looks like no big deal.
RoninSTI is offline   Reply With Quote
Old 08-07-2011, 02:37 AM   #5
Nimbus09
Scooby Specialist
 
Member#: 212399
Join Date: May 2009
Chapter/Region: NWIC
Location: portland, or
Vehicle:
09 wrx 301hp/328tq
'00 miata blue

Default

Quote:
Originally Posted by RoninSTI View Post
In case anyone else comes across this thread with the same issues, please read the following...

http://www.romraider.com/forum/topic5371.html

Section four describes what's going on better than I ever could. Looks like no big deal.
I'm not sure I would conclude that. I've seen pretty much the exact same thing on my stage 2 setup and I was losing coolant. Went back to stage 1, the tune didn't give me knock and now no more coolant loss. Knocking can supposedly lift heads, hence coolant loss. Not to scare you, but I want to see NO knock, especially learned which means the engine saw enough of it at that load/rpm that it had to put it in the learned knock table.

Also, my problems were exacerbated when I was using the HWG map. I'm on the regular stage 1 map currently, even though I'm slightly below target boost noted on the map notes.
Nimbus09 is offline   Reply With Quote
Old 08-07-2011, 10:02 AM   #6
Cobb Tuning
NASIOC Vendor
 
Member#: 4803
Join Date: Mar 2001
Location: Austin, DFW, Portland, SOCAL
Default

There is no such thing as a tune that will not have the occasional knock correction. Also, keep in mind that Subaru's knock detection system is a compromise between low cost and effectiveness. It will most certainly, at times, determine knock that is not present (i.e. false knock), especially at low loads/RPM.

A change to the fine knock learning is not any more severe than any other knock correction. Whether you see -1.4 deg correction in feedback knock correction or fine knock learning, it is still based on a single knock event (for ECUs that decrement these values by 1.4 deg). The ECU simply looks at certain conditions (such as the change in load) to determine which of the three knock responses to use (if any). The ECU places no level of severity on a given knock event - it is simply a perceived knock event or not at any given time.

Only a drop in the dynamic advance multiplier (DAM) (outside of the normal initial potentially lower value after a reflash/reset) is a potential indication of a more severe knock situation as fine knock learning must first hit extreme negative values before the DAM can drop (something that can occur quickly that you might not see in the logs).

That said, here's are some situations where the reported knock (in the logs) would be more of a concern:

1. A repeatable and consistent large feedback or fine correction (ex. -2.8) that is not at low loads and not immediately after mashing the throttle or shifting (say 1 or 2 lines in the log after the throttle event).

2. A repeatable and consistent feedback correction at wide open throttle not due to mashing the throttle or shifting.

3. A drop in the DAM that is not due to a reset, reflash or disconnecting the car's battery.

Bill
Cobb Tuning is offline   Reply With Quote
Old 08-07-2011, 12:54 PM   #7
Nimbus09
Scooby Specialist
 
Member#: 212399
Join Date: May 2009
Chapter/Region: NWIC
Location: portland, or
Vehicle:
09 wrx 301hp/328tq
'00 miata blue

Default

Quote:
Originally Posted by Cobb Tuning View Post
1. A repeatable and consistent large feedback or fine correction (ex. -2.8) that is not at low loads and not immediately after mashing the throttle or shifting (say 1 or 2 lines in the log after the throttle event).

2. A repeatable and consistent feedback correction at wide open throttle not due to mashing the throttle or shifting.


Bill
Bill,
I'm a little confused about these two points. Would fine knock learning not pull timing so you can NEVER get repeatable feedback correction?
Nimbus09 is offline   Reply With Quote
Old 08-07-2011, 01:43 PM   #8
Cobb Tuning
NASIOC Vendor
 
Member#: 4803
Join Date: Mar 2001
Location: Austin, DFW, Portland, SOCAL
Default

Quote:
Originally Posted by Nimbus09 View Post
Bill,
I'm a little confused about these two points. Would fine knock learning not pull timing so you can NEVER get repeatable feedback correction?
Feedback correction has no impact on fine knock learning or the DAM whatsoever. You could have -13 feedback knock and the correction would never be learned, nor would it impact fine knock learning or the DAM at all. Corrections in the fine knock learning table could help with feedback correction, but there is no direct link.

Only fine knock learning and the DAM are linked in that it requires extremes of fine knock learning for a change to the DAM to occur (other than after reflash/reset and some accelerated learning for the DAM in a positive direction for 2.5L ECUs). The entire fine knock learning table is cleared when the DAM changes. So, when changes to the DAM are active, the ECU will wait until the DAM settles and then switch to fine knock learning. Changes to fine knock learning are only active under certain conditions (such as steady load change). Feedback knock correction is the default correction and will come into play when the DAM/fine learning changes are not allowed (assuming feedback's RPM and load requirements are met).

Bill
Cobb Tuning 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
2011 sti stage 1 on AP question 08WRBsti AccessPort 16 05-19-2013 12:53 PM
2011 STI Stage 1+AEM vs Stage1+Cobb SF glamcem Factory 2.5L Turbo Powertrain 47 12-04-2011 12:41 AM
06 STi - Stage 1 OTS 93 - Knock @ 2800 RPM? This Is Not Mike AccessPort 4 04-10-2011 01:15 AM
Stage 1 OTS Map only hitting 11psi, vacuum is good. asrautox AccessPort 7 08-03-2008 07:33 PM
STi stage 2 basemap knocking 2.5 Blue Roo UTEC 6 07-24-2007 06:54 PM


All times are GMT -4. The time now is 09:00 PM.


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.