Welcome to the North American Subaru Impreza Owners Club Wednesday July 9, 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 > Open Source Reflashes

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 02-26-2008, 09:40 PM   #1
Kastley85891
Scooby Specialist
 
Member#: 127704
Join Date: Oct 2006
Chapter/Region: TXIC
Location: TX/Austin
Vehicle:
2013 Hybrid
Needs an 05STI

Default Suggested Max boost at different altitudes

Running an 06 STI, Dominator one with supporting 'bolt' on upgrades.

Currently at sea level 0n 91 oct with a little TORCO - usually target will be 21 psi, have run it at 22psi and it is fine, i.e. no log knock, (I get a little knock light action in the 4500-52500 area intermitantly at 22psi, still no recored log knock) correction etc, fueling is good, but do you think at 4500 ft this is running a little more then it should? just opinions, Im interested in how you more experienced guys would set your car up boost wise?

Part two, moving to sea level and 93 oct (no TORCO) assume 22 psi then would be a good max? again opinions, presuming my car run fines at 12.5 atm with 21psi
I know the total pressure will change etc but whats your guys personal preference
As ever
Thanks
* Registered users of the site do not see these ads.
Kastley85891 is offline   Reply With Quote
Old 02-26-2008, 09:52 PM   #2
testes1010
Scooby Specialist
 
Member#: 47145
Join Date: Nov 2003
Chapter/Region: MWSOC
Location: Henderson, KY
Vehicle:
2012 Gas Saver

Default

93octane @ near sea level I run 24psi daily w/ a TD05H-20G on a 2.0L, no knock with AFR of 11.4:1 at full load.
testes1010 is offline   Reply With Quote
Old 02-26-2008, 11:52 PM   #3
mickeyd2005
Scooby Newbie
 
Member#: 122595
Join Date: Aug 2006
Chapter/Region: NWIC
Vehicle:
2005 LGT Wagon
ABP

Default

Are you running a MBC?

If you're using the ecu to control boost, the ecu will automatically adjust your target boost. The only problem that might arise is if you are running a very high WG actuator spring. In that case, you will need to adjust your WGDC atmospheric compensation table.
mickeyd2005 is offline   Reply With Quote
Old 02-27-2008, 01:21 AM   #4
nhat
#Belieber
Moderator
 
Member#: 140163
Join Date: Feb 2007
Chapter/Region: MAIC
Location: 3MI Racing
Vehicle:
03 STi
hellaflunctional

Default

all the stage 2 stis in denver/boulder are maxing out around 16-17psi. my friend who's a tuner out there has his bugeye with a gt30r only running 16psi of boost on e85.

Last edited by nhat; 04-02-2008 at 01:25 PM.
nhat is offline   Reply With Quote
Old 02-27-2008, 01:49 AM   #5
vaccine
Scooby Newbie
 
Member#: 94490
Join Date: Aug 2005
Location: Australia
Default

maxing out what? sorry noob question!
i am running 22psi through a vf34/p20 with 3" zorst+avcr on an 02STi with 11.4AFR also.
everything else is stock. my tune is getting there. and 300g/sec is a bees foreskin away.
vaccine is offline   Reply With Quote
Old 02-27-2008, 02:40 PM   #6
Phatron
Scooby Guru
 
Member#: 36033
Join Date: Apr 2003
Chapter/Region: SCIC
Location: Tuning Lab
Vehicle:
CEO PhatBottiTuning
2006 STi GTX3582 + Meth

Default

I run 23-24psi on my 16g'd 02wrx on 91 octane at 3000ft.

I have also run 23-24psi on my green'd 06STi on 91 octane at 3000ft.
Phatron is offline   Reply With Quote
Old 02-27-2008, 02:51 PM   #7
Not-EWRX
Scooby Specialist
 
Member#: 158043
Join Date: Aug 2007
Chapter/Region: RMIC
Location: SLC
Vehicle:
2013 Wrx Hatch
SWP

Default

I sit at 4,327 and run 17lbs on the TD04. Knowledge of BCS tuning is critical at higher altitude.
Not-EWRX is offline   Reply With Quote
Old 03-01-2008, 01:23 PM   #8
LateApex31
Scooby Newbie
 
Member#: 135686
Join Date: Dec 2006
Chapter/Region: NESIC
Location: six- one-seven
Default

A compressor map will let you know what the compressor RPM will be at various pressure ratios. This will tell you exactly how much boost you can run.
LateApex31 is offline   Reply With Quote
Old 04-02-2008, 11:10 AM   #9
Dobbs
Scooby Newbie
 
Member#: 28291
Join Date: Oct 2002
Chapter/Region: RMIC
Vehicle:
2005 STi
Tuning Subarus in RMIC

Default

nail on the head apex... the TD04 (assuming that the 13T picture floating around is what is actually in the wrx) has a max pressure ratio of ~2.63 @ approx. 0.15m^3/s... in my experience at 7200ft, i traverse the left side of the compressor island, somewhere in the 73% efficiency region (look at the map, you'll see what i'm talking about). i am currently running 13psi max boost, and when atmospheric pressure here is ~11.4, that translates into a pressure ratio of 2.14 -- well under the limitations of peak efficiency of the turbo. i say find a map of the turbo you are running, check IDC's, and tune boost based upon a combo of your IDC and max pressure ratio...
Dobbs is offline   Reply With Quote
Old 04-02-2008, 11:20 AM   #10
chanders
Scooby Newbie
 
Member#: 131319
Join Date: Nov 2006
Chapter/Region: International
Vehicle:
2003 JDM STI
World Rally Blue

Default

^^ Wow, couldn't have read a better explanation. I run a IHI VF30 and its a b!tch to find compressor maps for it
chanders is offline   Reply With Quote
Old 04-02-2008, 02:26 PM   #11
mickeyd2005
Scooby Newbie
 
Member#: 122595
Join Date: Aug 2006
Chapter/Region: NWIC
Vehicle:
2005 LGT Wagon
ABP

Default

Even though compressor maps are based on PR, the ecu altitude compensation is based on percent reduction of the MAP target. You can change the modeling though. Some ecus use a table but some use a linear equation.
mickeyd2005 is offline   Reply With Quote
Old 04-02-2008, 11:54 PM   #12
GeneralTJI
Scooby Specialist
 
Member#: 152680
Join Date: Jun 2007
Location: s366 Duramax self built/tuned
Vehicle:
I Parted out WRX
for my Pilots License :)

Default

Kinda of depends on how you want to look at this... for example, I live at 6700ft altitude.. my vf39 WRX is making 18 maybe 19 psi on my boost gauge... however when logging, the actual manifold pressure my engine is seeing relative to sea level is in the 15psi (about 14.5psi at redline) area... So... I run my turbo as hard as I want to based off the gauge, even though of course at this altitude it's not making the same power, the turbo itself is still working very hard...

And yes.. it sucks living up here, however, there are a few things you can get away with.... im running 93% IDC now after I put on an STi TMIC, so I now need injectors, but I was "getting away" with stockers for a while... my driveline doesn't see quite as much abuse...clutch will hold a higher level of mods.... yet, when I go to the drag strip, I can slap LS1's around like nobody's business.... even though my times arn't as impressive
GeneralTJI 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 1 target boost at hight altitude chae1020 Newbies & FAQs 0 07-28-2009 12:44 PM
Boost at different MPHs or RPMs..... bfodle Factory 2.0L Turbo Powertrain 5 08-16-2005 08:31 AM
boost at high altitude battlebob19 Factory 2.0L Turbo Powertrain 6 03-15-2004 05:17 PM
Boost at altitude/temperature questions? Wombat North Factory 2.0L Turbo Powertrain 5 07-24-2002 01:32 AM
Boost pressure at high altitudes? 1ofeach Factory 2.0L Turbo Powertrain 5 02-04-2002 09:13 AM


All times are GMT -4. The time now is 11:23 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.