Welcome to the North American Subaru Impreza Owners Club Wednesday July 23, 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.
Reply
 
Thread Tools Display Modes
Old 09-06-2011, 02:21 PM   #1
mdefalco25
Scooby Newbie
 
Member#: 62985
Join Date: May 2004
Location: Normal, IL
Vehicle:
2005 STi
Platnium Silver

Default Need some help with regards to converting injectors

So I am in the process of converting my 05 STi to run e85. I am looking to convert my side feed injectors to top feed to assist with the idle and tune. Have heard enough horror stories on big side feed injectors and want to stick to what my tuner is good content with.

With that said, I am looking to do a fuel rail conversion kit of some sort but what I am struggling with is do I need to upgrade the fuel lines as well and are their pros and cons with going with high vs. low impedance injectors? I know P&Ls kit has the resistor box for the low imp. injectors so that is not my concern, but did not know if there was an easier way (cheaper) to just converting the rails and not messing with the fuel lines.

Please let me know your thoughts. I appreciate your help!
* Registered users of the site do not see these ads.
mdefalco25 is offline   Reply With Quote
Old 09-06-2011, 04:05 PM   #2
STIBungy
Scooby Specialist
 
Member#: 51684
Join Date: Jan 2004
Location: CO
Default

Depending on what your power goals are, going to topfeed might be going overboard.
STIBungy is offline   Reply With Quote
Old 09-06-2011, 05:04 PM   #3
mdefalco25
Scooby Newbie
 
Member#: 62985
Join Date: May 2004
Location: Normal, IL
Vehicle:
2005 STi
Platnium Silver

Default

Going with larger TMIC, larger intake, EWG and stock turbo. Really, just trying to get the most out of my stock turbo for the moment. Wanted to stick with 850cc but hear e85 will need more than that.
mdefalco25 is offline   Reply With Quote
Old 09-06-2011, 09:40 PM   #4
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

Depends on your turbo. 850cc injectors will bring you to maybe 350-370whp on E85.
the suicidal eggroll is offline   Reply With Quote
Old 09-06-2011, 09:44 PM   #5
mdefalco25
Scooby Newbie
 
Member#: 62985
Join Date: May 2004
Location: Normal, IL
Vehicle:
2005 STi
Platnium Silver

Default

Stock turbo build... Will probably not upgrade turbo and if I do then would go bigger injectors. Just trying to figure out if I can use 850cc instead for stock turbo and still make some power.
mdefalco25 is offline   Reply With Quote
Old 09-06-2011, 09:49 PM   #6
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

Stock turbo should be alright on 850. You don't need to convert to top feed for 850cc either, waste of money IMO. Now if you were going to 1200cc+, then sure, but not for 850.
the suicidal eggroll is offline   Reply With Quote
Old 09-06-2011, 10:02 PM   #7
mdefalco25
Scooby Newbie
 
Member#: 62985
Join Date: May 2004
Location: Normal, IL
Vehicle:
2005 STi
Platnium Silver

Default

well, I was under the impression that 850cc would be too small hence the question on converting to top feeds. With the bigger intake, TMIC and EWG was not sure if 850cc would carry me, but for the money to convert wondering if it would be overkill which it sounds like it is. Thanks for your input!
mdefalco25 is offline   Reply With Quote
Old 09-06-2011, 10:19 PM   #8
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

It'll be close. Personally I'd go for more like 1000cc. I was just saying that if you're going to get 850cc regardless, then there's no reason to switch to top feed.
the suicidal eggroll is offline   Reply With Quote
Old 09-06-2011, 10:30 PM   #9
mdefalco25
Scooby Newbie
 
Member#: 62985
Join Date: May 2004
Location: Normal, IL
Vehicle:
2005 STi
Platnium Silver

Default

If I go any bigger than they will not be easy to tune for 93 oct. Hence why I was going to do the top feed conversion... I am fine with converting my injectors to top feed, but don't want to upgrade fuel lines if not necessary hence my original question
mdefalco25 is offline   Reply With Quote
Old 09-06-2011, 10:41 PM   #10
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

You don't need to upgrade lines, but you might need some spare 5/16" fuel line to run from the hard lines to the top feed rails, if they don't line up in the same place as the side feed rails.

You'll need a DW301 or Aeromotive 340 pump as well, the Walbro can't flow that much.
the suicidal eggroll is offline   Reply With Quote
Old 09-06-2011, 11:06 PM   #11
mdefalco25
Scooby Newbie
 
Member#: 62985
Join Date: May 2004
Location: Normal, IL
Vehicle:
2005 STi
Platnium Silver

Default

That is what I was looking for! Thanks. Already got the Aeromotive 340, forgot to mention that. But thanks for the heads up!
mdefalco25 is offline   Reply With Quote
Old 10-04-2012, 11:54 AM   #12
Scuby04STi
Scooby Newbie
 
Member#: 328635
Join Date: Aug 2012
Chapter/Region: NWIC
Location: Portland*
Vehicle:
2004 STi GTX3076R
Rally Blue

Default

One thing to remember is that most top feed set ups change to a different end connections, and change the way the hoses are run to distribute the fuel more evenly.
Scuby04STi is offline   Reply With Quote
Old 10-04-2012, 12:21 PM   #13
kellygnsd
Scooby Guru
 
Member#: 32669
Join Date: Feb 2003
Chapter/Region: SCIC
Location: Rancho C
Vehicle:
2007 2.34LR, EFR7670
LINK G4 hybrid STi

Default

Quote:
Originally Posted by Scuby04STi View Post
One thing to remember is that most top feed set ups change to a different end connections, and change the way the hoses are run to distribute the fuel more evenly.
If you're talking about the parallel fuel rail mod that can be done on top feed as well as side feed setups.
kellygnsd is offline   Reply With Quote
Old 10-04-2012, 12:34 PM   #14
Scuby04STi
Scooby Newbie
 
Member#: 328635
Join Date: Aug 2012
Chapter/Region: NWIC
Location: Portland*
Vehicle:
2004 STi GTX3076R
Rally Blue

Default

Yes, and I know. Just from reading it looked like the plan was to use the stock lines that in most kits are replaced for that specific reason. fuel issue #1 on an STi is that unparalleled stock set up, issue #2 are the side feeds with big injectors. So IMO no point on worrying about the second if you ignore the first.

This is only concerning the fuel system section mounted to the engine not the pump and such.

Last edited by Scuby04STi; 10-04-2012 at 12:36 PM. Reason: missed a point
Scuby04STi is offline   Reply With Quote
Old 10-04-2012, 12:47 PM   #15
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

The series rails really aren't that big a deal until you get to very large fuel pump setups, at which point you should probably be swapping out the FPR and rails anyway.
the suicidal eggroll is offline   Reply With Quote
Old 10-04-2012, 01:37 PM   #16
Scuby04STi
Scooby Newbie
 
Member#: 328635
Join Date: Aug 2012
Chapter/Region: NWIC
Location: Portland*
Vehicle:
2004 STi GTX3076R
Rally Blue

Default

I agree, but based on cost and the changes he is already looking into why not change that when your changing most the other problem areas?
Scuby04STi is offline   Reply With Quote
Old 10-04-2012, 01:51 PM   #17
Leafy
Scooby Specialist
 
Member#: 330625
Join Date: Aug 2012
Chapter/Region: NESIC
Location: MA
Vehicle:
2006 WRX
WRB

Default

On the low vs high impedance thing, with the ev14's now I wouldnt even consider low imp injectors unless the car was already setup to run them. Buy ev14s and your tuner will love you, the big 2000cc ones can idle like stock on most cars.
Leafy is offline   Reply With Quote
Old 10-04-2012, 04:37 PM   #18
funk32
NASIOC Supporter
 
Member#: 245787
Join Date: May 2010
Chapter/Region: W. Canada
Location: Canada
Vehicle:
2004 STi
PSM

Default

funk32 is offline   Reply With Quote
Old 10-04-2012, 04:39 PM   #19
the suicidal eggroll
Scooby Guru
 
Member#: 51961
Join Date: Jan 2004
Chapter/Region: RMIC
Location: Broomfield, CO
Vehicle:
2005 STi
2012 WRX

Default

Quote:
Originally Posted by funk32 View Post
They're good, but I would buy them from T1 direct, since they're the ones who actually helped develop the kit (along with Maxwell I believe), and will be much better able to answer any questions you may have:
http://www.t1racedevelopment.com/ind...04-06-sti.html

KEEP IN MIND that this is not a real top feed conversion kit, it will ONLY work with the ID injectors that have been specifically modified to work with those rails. The kit works great, but just be aware that if you decide you want to swap to some different top feed injectors later on, it'll have to be to one of the few specially-modified ID ones that are designed for this kit. You can't just swap in any top feed of the street. Even though it's not on their site, T1 will separately sell you the ID injectors that work with this kit (if you want to change sizes), just call and ask.

Last edited by the suicidal eggroll; 10-04-2012 at 04:44 PM.
the suicidal eggroll is offline   Reply With Quote
Old 10-04-2012, 07:08 PM   #20
CobbsSTI
Scooby Specialist
 
Member#: 245242
Join Date: Apr 2010
Chapter/Region: MWSOC
Location: Morris,IL
Vehicle:
2006 STI
E85 Power

Default

I did the T1 race development top feed conversion kit on my 06 STI and I love it. The install wasn't to bad, with the plug n play adapters, lines, rails and injectors. I went with 1000cc injectors running E85 and love them. I made the mistake going with bigger sidefeeds, more like sidefails. The T1 kit is awesome. Highly recommend it.
CobbsSTI is offline   Reply With Quote
Old 10-04-2012, 08:20 PM   #21
k mier
Scooby Specialist
 
Member#: 98000
Join Date: Oct 2005
Location: MO
Vehicle:
05 sti e85@420hp

Default

With the larger fuel pump and e85 the 850's should be enough with the vf39. The 850's are easy to find and relatively cheap. The 850's got me to 434 @ 99% duty cycle, backed off to 420 w/low 90% duty cycle. Stock fuel lines and rails.
k mier 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
Any Clark Turner customers? Need some help with what to go with! DJS_02_WRX Newbies & FAQs 50 12-04-2009 09:55 AM
Need some help with Drum to Disc on a FWD stickfiguredanny Brakes, Steering & Suspension 0 11-09-2007 10:30 PM
Need some helpful info regarding collision repairs and insurance. mpaone South East Region Forum 4 08-18-2005 08:53 AM
Long Island OT'erz I need some help with Getting to Greenport MidnightSti05 Off-Topic 18 05-26-2005 11:03 PM
need some help with modded injectors mwrxmax Engine Management & Tuning 7 06-09-2004 07:45 PM


All times are GMT -4. The time now is 02:40 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.