STI Forum  |  Shop  |  Sponsors  |  Advertise Rules  |  FAQ  |  Members List  |  Calendar
IWSTI.com: Subaru WRX STI Forums
 
Home  |  Register  |  Today's Posts  |  Go Premium Mark Forums Read Create a Member Journal  |  Vendor Deals  |  Member Classifieds
 
Register at IWSTI.com for FREE
Refer IWSTI.com to a friend
Go Back   IWSTI.com: Subaru WRX STI Forums > IWSTI Engine & Drivetrain > ECU Tuning & Performance Electronics > Cobb Street Tuner


Reply
 
Thread Tools
Old 05-13-2006, 01:50 PM   #1
Silver Member
 
Car: 2005 STI
Fav Mod: Shawn's brain
Location: Southwest Michigan
Posts: 419
IWSTI Addict since: Aug 2004
Trader Rating: (0)
Default What is the most boost you have logged with ST?

Seems like a silly question but...

I have been tinkering with wastgate duty cycles again. I have noticed a few pulls hit 20psi according to my Omori boost gauge but when I check the log it only shows 18.42. As a matter of fact, I have never seen the boost over 18.42 in a data log even though the Omori shows it higher.

Any ideas?

Thanks,

Jeff B


This ad is not endorsed by this member. Please register or login to hide this ad.
TurboQueef is offline   Reply With Quote
Old 05-13-2006, 01:53 PM   #2
DOMINATOR
 
Fav Mod: Strut Clunk
Location: STL
Posts: 5,644
IWSTI Addict since: May 2005
Trader Rating: (5)
Default

Quote:
Originally Posted by TurboQueef
Seems like a silly question but...

I have been tinkering with wastgate duty cycles again. I have noticed a few pulls hit 20psi according to my Omori boost gauge but when I check the log it only shows 18.42. As a matter of fact, I have never seen the boost over 18.42 in a data log even though the Omori shows it higher.

Any ideas?

Thanks,

Jeff B
I think the ecu can only read that high, so if you did actually go over ~18.42 the ecu would only show that number.
Muffnbluff is offline   Reply With Quote
Old 05-13-2006, 07:07 PM   #3
Spec C Club
 
Fav Mod: 4th gear wheelspin
Location: Upstate NY
Posts: 2,095
IWSTI Addict since: Nov 2004
Trader Rating: (0)
Default

36.69 absolute.
jays05 is offline   Reply With Quote
Old 05-13-2006, 07:26 PM   #4
Silver Member
 
Car: 2005 STI
Fav Mod: Shawn's brain
Location: Southwest Michigan
Posts: 419
IWSTI Addict since: Aug 2004
Trader Rating: (0)
Default

Quote:
Originally Posted by jaygoesfast
36.69 absolute.
??????
TurboQueef is offline   Reply With Quote
Old 05-13-2006, 07:30 PM   #5
Junior STI Driver
 
Car: 04 STi
Fav Mod: Track experience
Posts: 144
IWSTI Addict since: Apr 2006
Trader Rating: (0)
Default

Quote:
Originally Posted by Muffnbluff
I think the ecu can only read that high, so if you did actually go over ~18.42 the ecu would only show that number.
What he said: try a search over at wrxforum.com I remeber christian (cobb guy) talking about it once. The short of it, the ecu only recognizes ~18.3 psi
Dr. Gonzo is offline   Reply With Quote
Old 05-13-2006, 07:32 PM   #6
Visiting NASIOC Timeout
 
Car: 05 STi + 08 OBXT
Fav Mod: Wingless FTW!
Location: Jacksonville, FL
Posts: 6,123
IWSTI Addict since: May 2004
Trader Rating: (2)
Default

Subtract 14.7 atmostpheric pressure from 36.7 psia, and you'll get 22 psig.

The most I've logged on my UTEC is 20 psig. (It was a snap cold spell, and I was still running my warm weather map.)
Datadatum is offline   Reply With Quote
Old 05-13-2006, 08:05 PM   #7
Spec C Club
 
Fav Mod: 4th gear wheelspin
Location: Upstate NY
Posts: 2,095
IWSTI Addict since: Nov 2004
Trader Rating: (0)
Default

I think 36.69 is the max reading on the MAP sensor - it sure looks like it from my datalogs.
jays05 is offline   Reply With Quote
Old 05-14-2006, 11:48 AM   #8
Moderator & ECU Tech
 
Fav Mod: mo boostaz
Location: Fredneck, MD
Posts: 3,759
IWSTI Addict since: Jun 2004
Trader Rating: (6)
Default

Log Atmospheric Pressure and Absolute pressure. I stopped logging relative pressure a long time ago. Open up the log in Excel and subtract the atmospheric pressure from the absolute pressure. There ya go.

t
WolfPlayer is offline   Reply With Quote
Old 05-14-2006, 05:12 PM   #9
Silver Member
 
Car: 2005 STI
Fav Mod: Shawn's brain
Location: Southwest Michigan
Posts: 419
IWSTI Addict since: Aug 2004
Trader Rating: (0)
Default

Quote:
Originally Posted by WolfPlayer
Log Atmospheric Pressure and Absolute pressure. I stopped logging relative pressure a long time ago. Open up the log in Excel and subtract the atmospheric pressure from the absolute pressure. There ya go.

t
Cool, that is the ticket.. thanks
TurboQueef is offline   Reply With Quote
Old 05-14-2006, 11:42 PM   #10
Senior STI Driver
 
Car: 2005 WRB STi
Fav Mod: roadhead
Location: Grand Rapids, MI
Posts: 314
IWSTI Addict since: Dec 2005
Trader Rating: (0)
Send a message via AIM to overdose Send a message via MSN to overdose Send a message via Yahoo to overdose
Default

Quote:
Originally Posted by TurboQueef
Cool, that is the ticket.. thanks
Yup, absolute-relative = real boost, just use the sum function in excel to make a corrected column

sidenote i just installed a big tmic so i'm gonna be goin for 22psi on pump gas :P


This ad is not endorsed by this member. Please register or login to hide this ad.
overdose is offline   Reply With Quote
 
Reply

Thread Tools

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


New To Site? Need Help? More

All times are GMT -8. The time now is 01:17 AM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
Designed & Powered by Domain Architect