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 > Factory 2.5L Turbo Powertrain

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.
Closed Thread
 
Thread Tools Display Modes
Old 02-18-2008, 02:58 PM   #1
Wrinkleboi
Top Scoob 006
 
Member#: 14424
Join Date: Jan 2002
Chapter/Region: South East
Location: Stuart, FL
Vehicle:
BugI w/ 07 STi Swap
www.TriStateTuners.com

Default 07 STi with 8cm FP Green, EWG, headers, etc... 750cc or 850cc injectors?

I know the 07 STi fueling is a little different than its 04-06 STi counterpart, and I'm trying to decide on injector sizing for my setup. I'm deciding between Deatschwerks 750cc or 850cc top feed injectors. The 750cc are cheaper and I think they'll do the job, but I'd hate to find out I was wrong when my car's strapped to the dyno.
First, are there any drawbacks to going larger like difficulty of tune or rougher idle?
And finally, what do you think for this setup:

07 STi
3"/8cm FP Green
APS 70mm CAI
APS Turbo Inlet
APS DR525 FMIC
TGV Delete
Perrin Headers
TurboXS EWG Uppipe
TiAL 44mm EWG
HKS Downpipe
APS Catback
Walbro Fuel Pump
___cc Injectors?

I will be running an Aquamist water/meth injection setup as well but I dont want to have to rely on it in order to not run out of fuel.

If you can, please post reasoning to go along with your answer, or past experience with similar setups. Unfortunately I know the 07 STi specific stuff isn't as widespread.
* Registered users of the site do not see these ads.
Wrinkleboi is offline  
Old 02-18-2008, 03:11 PM   #2
dexterous
Scooby Guru
 
Member#: 23553
Join Date: Aug 2002
Chapter/Region: MAIC
Location: Slippery Rock, PA
Vehicle:
2005 STI - Insanity!
2014 WRX - Daily

Default

I had 860cc injectors on my stock turbo 05 sti setup and it ran perfectly. I would strongly recommend that you go 860.
dexterous is offline  
Old 02-18-2008, 03:25 PM   #3
nhat
Scooby Guru
 
Member#: 140163
Join Date: Feb 2007
Chapter/Region: MAIC
Location: 3MI Racing
Vehicle:
03 STi
hellaflunctional

Default

i would personally go for headroom.

Quote:
Originally Posted by dexterous View Post
I had 860cc injectors on my stock turbo 05 sti setup and it ran perfectly. I would strongly recommend that you go 860.
good to know. i just picked up a set of pe850s to go into my car with the stock turbo
nhat is offline  
Old 02-18-2008, 05:04 PM   #4
PowerTrip
Scooby Specialist
 
Member#: 158674
Join Date: Sep 2007
Chapter/Region: SCIC
Location: Irvine, CA
Vehicle:
'15 STi Limited
DGM

Default

I run DW850's on my stock turbo stage 2 set-up and it runs perfectly and idles smoothly. Headroom FTW
PowerTrip is offline  
Old 02-18-2008, 05:45 PM   #5
jordanretro1223
Scooby Guru
 
Member#: 143039
Join Date: Mar 2007
Chapter/Region: MAIC
Location: Delaware
Vehicle:
2007 STI
Satin White Pearl

Default

Quote:
Originally Posted by PowerTrip View Post
I run DW850's on my stock turbo stage 2 set-up and it runs perfectly and idles smoothly. Headroom FTW
I agree here.

Get a different DP though....
jordanretro1223 is offline  
Old 02-18-2008, 05:50 PM   #6
subenerd
Scooby Specialist
 
Member#: 72630
Join Date: Oct 2004
Location: CA
Vehicle:
2004 STi

Default

You need to ask your tuner.
subenerd is online now  
Old 02-18-2008, 06:05 PM   #7
Wrinkleboi
Top Scoob 006
 
Member#: 14424
Join Date: Jan 2002
Chapter/Region: South East
Location: Stuart, FL
Vehicle:
BugI w/ 07 STi Swap
www.TriStateTuners.com

Default

Quote:
Originally Posted by jordanretro1223 View Post
I agree here.

Get a different DP though....
are you telling me to get a different downpipe? i specifically chose to run this downpipe with my EWG setup because it reduces turbulence that would be caused by a bellmouth (which would be necessary for internal wastegate, but not for me). i even went as far as having a tab welded onto it to block off the internal wastegate area of the turbo since it is not being used.

thanks for the responses... seems that the 750cc should be fine but also sounds now like there are no drawbacks to the 850cc except for being $100 more.

Last edited by Wrinkleboi; 02-18-2008 at 06:22 PM.
Wrinkleboi is offline  
Old 02-18-2008, 06:11 PM   #8
nhat
Scooby Guru
 
Member#: 140163
Join Date: Feb 2007
Chapter/Region: MAIC
Location: 3MI Racing
Vehicle:
03 STi
hellaflunctional

Default

i know of a performance shop selling a set of helix 820cc topfeeds for $100 if you're interested.
nhat is offline  
Old 02-18-2008, 06:36 PM   #9
4ST-AIR
Scooby Specialist
 
Member#: 148681
Join Date: May 2007
Chapter/Region: MWSOC
Location: WI
Vehicle:
TBD Looking for STI
Back in the Game!

Default

Quote:
Originally Posted by subenerd View Post
You need to ask your tuner.
+1 on that your tuner has to work with your goals ask your tuner what he/she prefers to tune.

I have modded OEM's to 920cc's and I idle at about 900rpms but its a smooth idle nothing rough about it.
4ST-AIR is offline  
Old 02-18-2008, 08:34 PM   #10
jordanretro1223
Scooby Guru
 
Member#: 143039
Join Date: Mar 2007
Chapter/Region: MAIC
Location: Delaware
Vehicle:
2007 STI
Satin White Pearl

Default

Quote:
Originally Posted by Wrinkleboi View Post
are you telling me to get a different downpipe? i specifically chose to run this downpipe with my EWG setup because it reduces turbulence that would be caused by a bellmouth (which would be necessary for internal wastegate, but not for me). i even went as far as having a tab welded onto it to block off the internal wastegate area of the turbo since it is not being used.

thanks for the responses... seems that the 750cc should be fine but also sounds now like there are no drawbacks to the 850cc except for being $100 more.
Alright well I stand corrected then bro. That seems like a good setup then. And since you are doing an EWG your plan makes perfect sense.

Good luck with the build.
jordanretro1223 is offline  
Old 02-18-2008, 10:09 PM   #11
Wrinkleboi
Top Scoob 006
 
Member#: 14424
Join Date: Jan 2002
Chapter/Region: South East
Location: Stuart, FL
Vehicle:
BugI w/ 07 STi Swap
www.TriStateTuners.com

Default

thanks...

i was waiting to hear back from my tuner and now i did... he said either should be fine but like what was said here, there arent any real drawbacks to going bigger.
Wrinkleboi is offline  
Old 02-18-2008, 10:35 PM   #12
iRace559
Scooby Specialist
 
Member#: 142654
Join Date: Mar 2007
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2007 OBP WRX RA 1-4
Built Motor DOM3XT-R :)

Default

Quote:
Originally Posted by nhat View Post
i know of a performance shop selling a set of helix 820cc topfeeds for $100 if you're interested.
Pmmed.
iRace559 is offline  
Old 02-28-2012, 11:27 PM   #13
StupidFastWagon
Scooby Specialist
 
Member#: 157526
Join Date: Aug 2007
Vehicle:
2014 335i xDrive
M Sport

Default

Get some 1000cc and call it a day, Gives you good head room if you want to go bigger or switch to race fuels later on
StupidFastWagon is offline  
Old 02-29-2012, 01:47 AM   #14
2Fast4U1DAY
Scooby Specialist
 
Member#: 250152
Join Date: Jun 2010
Chapter/Region: MAIC
Location: Pennsylvania
Vehicle:
2006 WRX Limited
OBP

Default

Quote:
Originally Posted by Wrinkleboi
thanks...

i was waiting to hear back from my tuner and now i did... he said either should be fine but like what was said here, there arent any real drawbacks to going bigger.
It really depends on your power goals as to whether 750's or 850's would be better for your setup. IMO if you are going to shoot for 400+ you should go 1000's leave yourself plenty of headroom to upgrade later down the road, and keeps your IDC's down. 850's are going to be pushed more than the 1000's, but you will definately run out of fuel on 750's before you run out of turbo.
2Fast4U1DAY is offline  
Old 02-29-2012, 09:29 AM   #15
Zee Biker
Scooby Specialist
 
Member#: 166005
Join Date: Dec 2007
Chapter/Region: MWSOC
Location: Northern 'Burbs
Vehicle:
2005 Saab 92x
Beaten Silver

Default

1. This is 4 years old. 4 years?!

2. How and why did you chime in after so many other responses? After 4 years.

3. The car just got tuned, with results posted in the PPB.

Shocked.
Zee Biker is offline  
Closed Thread

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
750cc or 850cc Injectors? Coop1103 Factory 2.5L Turbo Powertrain 24 10-24-2009 06:27 PM
07 STI FP GREEN EWG 370/388 @23psi Slimsti Proven Power Bragging 25 03-20-2009 09:04 AM
WTB: Injen CAI, 750cc or 850cc Injectors Sideways76 Private 'Wanted' Classifieds 2 01-29-2009 07:31 AM
fp green, ewg, fmic, injectors, gauges, etc Almost_there_1 Engine/Power/Exhaust 61 08-16-2008 02:17 AM
Looking for an FP Green & a set of 750cc or 850cc injectors 03SuBbYWrX Private 'Wanted' Classifieds 3 10-24-2007 07:23 PM


All times are GMT -4. The time now is 02:48 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.