Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo)

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.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 11-28-2012, 02:56 PM   #1
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default Strange RPM Cut/Rev limit issue

So I'm tuned on Open Source and I'm currently retuning on the Cobb AccessPort. In OS we were able to rev out to 7250 before the car stops revving (seems like a cut/limiter is being hit).

Now fast forward to Cobb Accessport tuning. Same base map, but the car stops revving at 6500rpm Makes no sense. If I have a mechanical problem I can understand not being able to rev past 7250rpm in both OS and Accessport...but what's up with the Accessport not letting me rev past 6500rpm? There's a 750rpm difference, but the base tune is the exact same. I have all of the same limits, dtc turned off, everything matches up with the open source tune.

Tuning

Speed Density
Rev limit set at 7500rpm
Boost limit 32psi
Launch Control turned off
FF Shifting turned off


Mods:
Built SB
Stock heads
Full Race twinscroll kit



I changed and regapped my plugs. Cleaned the Crank sensor. I'm not out of fuel. Heck, when I free rev in neutral it still cuts at 6500rpm. Don't know what else to look for at this point.

***I posted this in the Tuning section as well. I think the 750rpm delta between OS and Cobb AP may possibly be tune related while the hard limit (7250rpm) may be hardware/mechanical issues.***
* Registered users of the site do not see these ads.
wgr73 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 11-28-2012, 04:44 PM   #2
Leafy
Scooby Specialist
 
Member#: 330625
Join Date: Aug 2012
Chapter/Region: NESIC
Location: MA
Vehicle:
2006 WRX
WRB

Default

Is it acting like a fuel cut limiter (ie wideband going nuts, not much popping), a spark cut limiter (ie, wideband going nuts, loud popping), or a throttle limiter (wideband stays kind of normal just sounds and acts like you eased off the throttle)?
Leafy is offline   Reply With Quote
Old 11-28-2012, 05:02 PM   #3
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default

Quote:
Originally Posted by Leafy View Post
Is it acting like a fuel cut limiter (ie wideband going nuts, not much popping), a spark cut limiter (ie, wideband going nuts, loud popping), or a throttle limiter (wideband stays kind of normal just sounds and acts like you eased off the throttle)?
By your explanations it's throttle limiting. Wbo2 is solid until I let off. Load drops of course, feels like it stops making power. It'll overrun up to 7k but stable off at 6500. I'll post a log
wgr73 is offline   Reply With Quote
Old 11-28-2012, 05:30 PM   #4
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default

The only thing I see is on the Y-Axis for RPM on the throttle map that it's scaled to 6800. But I believe the AP will use the last cell for anything past 6800rpm...so it shouldn't matter
wgr73 is offline   Reply With Quote
Old 11-30-2012, 10:44 AM   #5
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default

Update: So the longer than I hold the throttled down the more violent it gets, bucks but no knock!....and afr does go crazy. I logged TPS, APS, Inj pw. Ill look at the log in a bit. Thinking its a fuel/spark cut now
wgr73 is offline   Reply With Quote
Old 12-01-2012, 05:57 PM   #6
atomicfire
Scooby Specialist
 
Member#: 136296
Join Date: Dec 2006
Chapter/Region: TXIC
Location: Midtown, Houston, TX
Vehicle:
2005 STi
OBP

Default

might have more luck in the tuning forum
atomicfire is offline   Reply With Quote
Old 12-02-2012, 12:25 PM   #7
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default

Thanks. I have a thread there as well
wgr73 is offline   Reply With Quote
Old 12-02-2012, 04:47 PM   #8
Tripintaz
Scooby Specialist
 
Member#: 245218
Join Date: Apr 2010
Chapter/Region: South East
Location: FL
Vehicle:
2013 STI Limited

Default

There is another table that has to be adjusted when raising the rev limiter using Cobb ATR. If you go to their site and review the advanced tuning document this is reviewed in detail.
Tripintaz is offline   Reply With Quote
Old 12-03-2012, 03:57 PM   #9
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default

Quote:
Originally Posted by Tripintaz View Post
There is another table that has to be adjusted when raising the rev limiter using Cobb ATR. If you go to their site and review the advanced tuning document this is reviewed in detail.
Ok thanks, ill check it out.
wgr73 is offline   Reply With Quote
Old 12-04-2012, 10:35 AM   #10
banshee04
Scooby Specialist
 
Member#: 179014
Join Date: May 2008
Location: Oklahoma City, OK
Vehicle:
'06 WRX/STi
Built Motor/6766/E85

Default

Ive been fighting the exact same problem for awhile now, but im using OS. About a year ago when I had a 20G on the car, I could rev as high as I wanted to. Once I started doing bigger turbo setups, thats where it started. It just doesnt go past 7000rpms whether im in neutral or in gear. All the DBW settings are exactly the same as when I had the 20G. Its starting to get me pretty stumped.

Last edited by banshee04; 12-04-2012 at 06:34 PM.
banshee04 is offline   Reply With Quote
Old 12-07-2012, 12:21 PM   #11
wgr73
Scooby Specialist
 
Member#: 232458
Join Date: Dec 2009
Chapter/Region: SWIC
Location: Las Cruces/El Paso
Vehicle:
2005 & 2008 STi
Cobb 20g & EFR 7670

Default

I have another thread (HERE)
wgr73 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

All times are GMT -4. The time now is 02:33 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.