Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

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 04-22-2016, 05:06 PM   #1
Bjwilson1993
Scooby Newbie
 
Member#: 383734
Join Date: Mar 2014
Chapter/Region: NWIC
Location: Salem, Oregon
Vehicle:
1995 Legacy Outback
Green/ Matte Black

Default Building hybrid for 02 wrx. Questions.

Okay so we're going with a forged short block. (Forged rods and Pistons) http://m.ebay.com/itm/272213507269

Going to port and polish the heads with stage 2 cams https://www.rallysportdirect.com/fit...-272-camshafts

and double spring valve springs.

New headers and up pipe. New Downpipe don't know what turbo to get yet ( please give some suggestions based on build)

Front mount intercooler possibly 555cc injectors. And upgraded fuel pump and obviously a healthy tuning.

Any constructive criticism or ideas are greatly appreciated.
* Registered users of the site do not see these ads.
Bjwilson1993 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 04-22-2016, 07:23 PM   #2
ripman
Scooby Newbie
 
Member#: 305707
Join Date: Jan 2012
Chapter/Region: International
Location: AUS
Vehicle:
1999 WRX
WRC Blue

Default

Get the heads chamber matched to the 2.5 bore size.
ripman is offline   Reply With Quote
Old 04-22-2016, 10:54 PM   #3
danger1138
Scooby Specialist
 
Member#: 279525
Join Date: Apr 2011
Chapter/Region: Tri-State
Location: QUEENS NY
Vehicle:
06 Fxt

Default Building hybrid for 02 wrx. Questions.

What turbo do you plan on running?.. Oops never mind, just read whole thread (aka; point of this thread)..

Id suggest upgrade to at least running 750cc injectors or higher, that way you could atleast support 18g power (i would recommend that sized turbo with your setup,) . That along with the mods you already have waiting to be installed should make for a very fun DD. After the tune obviously.

Last edited by danger1138; 04-22-2016 at 10:59 PM.
danger1138 is offline   Reply With Quote
Old 04-23-2016, 02:00 PM   #4
Ryan314
Scooby Guru
 
Member#: 82989
Join Date: Mar 2005
Chapter/Region: SWIC
Location: Arizona
Vehicle:
2002 WRX
Hybrid EJ257

Default

Quote:
Originally Posted by ripman View Post
Get the heads chamber matched to the 2.5 bore size.
This is the most important aspect of a hybrid build.
Ryan314 is offline   Reply With Quote
Old 04-23-2016, 10:33 PM   #5
Bjwilson1993
Scooby Newbie
 
Member#: 383734
Join Date: Mar 2014
Chapter/Region: NWIC
Location: Salem, Oregon
Vehicle:
1995 Legacy Outback
Green/ Matte Black

Default

Will I have to get new fuel rails for the 750cc injectors? Or will stock setup fit?
Bjwilson1993 is offline   Reply With Quote
Old 04-23-2016, 10:38 PM   #6
Bjwilson1993
Scooby Newbie
 
Member#: 383734
Join Date: Mar 2014
Chapter/Region: NWIC
Location: Salem, Oregon
Vehicle:
1995 Legacy Outback
Green/ Matte Black

Default Building hybrid for 02 wrx. Questions.

Know any shops in Oregon mid valley area that will chamber match or can I just take the head with a head gasket from the 257 to a machine shop with a CNC machine?
Bjwilson1993 is offline   Reply With Quote
Old 04-24-2016, 05:12 PM   #7
ripman
Scooby Newbie
 
Member#: 305707
Join Date: Jan 2012
Chapter/Region: International
Location: AUS
Vehicle:
1999 WRX
WRC Blue

Default

The head gasket is bigger than the bore. I usually pin the gasket on then run a bit of mig wire around inside it and mark it that way.
ripman is offline   Reply With Quote
Old 04-24-2016, 06:10 PM   #8
04ScoobyWtf
Scooby Specialist
 
Member#: 287974
Join Date: Jul 2011
Default

With my hybrid i didnt chber match at all. I used a cometic 2x thickness hg and that is all.
Specs are 9.0:1 wiseco 100mm pistons, eagle rods, stock crank, arp headstuds, 2x thick cometic hg, stock refreshed heads, 565cc ingectors and vf39. Makes just under 300 at the wheel with crazy off boost torque due to high cr. Due to the high cr i did have to dial down the timing or else i would have made more whp. If i was to do it all over i would simply deburr the heads and run a 8.2:1 piston.

Im also at 25k miles on the build

Last edited by 04ScoobyWtf; 04-24-2016 at 06:32 PM.
04ScoobyWtf is offline   Reply With Quote
Old 04-24-2016, 07:46 PM   #9
danger1138
Scooby Specialist
 
Member#: 279525
Join Date: Apr 2011
Chapter/Region: Tri-State
Location: QUEENS NY
Vehicle:
06 Fxt

Default

Quote:
Originally Posted by 04ScoobyWtf View Post
With my hybrid i didnt chber match at all. I used a cometic 2x thickness hg and that is all.
Specs are 9.0:1 wiseco 100mm pistons, eagle rods, stock crank, arp headstuds, 2x thick cometic hg, stock refreshed heads, 565cc ingectors and vf39. Makes just under 300 at the wheel with crazy off boost torque due to high cr. Due to the high cr i did have to dial down the timing or else i would have made more whp. If i was to do it all over i would simply deburr the heads and run a 8.2:1 piston.

Im also at 25k miles on the build

I agree with this method. I machined my heads when i went the hybrid route. It has lasted me 90k and counting but ^ this method right here is another route you can take. If you read thru the forums in regards to hybrid builds you will realize that machining your heads isnt the only method for achieving success.
danger1138 is offline   Reply With Quote
Old 04-25-2016, 01:29 AM   #10
Bjwilson1993
Scooby Newbie
 
Member#: 383734
Join Date: Mar 2014
Chapter/Region: NWIC
Location: Salem, Oregon
Vehicle:
1995 Legacy Outback
Green/ Matte Black

Default

Rip this is a big job for a friend so I don't want to really do the machining myself as I am not an experienced machiner. All I've done is port my heads on my 98 DOHC
Bjwilson1993 is offline   Reply With Quote
Old 04-25-2016, 01:39 AM   #11
Bjwilson1993
Scooby Newbie
 
Member#: 383734
Join Date: Mar 2014
Chapter/Region: NWIC
Location: Salem, Oregon
Vehicle:
1995 Legacy Outback
Green/ Matte Black

Default Building hybrid for 02 wrx. Questions.

Would the cosmetic 040 HGs work for me? Or are we talking about the ones that are like 1.5thick
http://www.carid.com/cosworth/high-p...FceCfgodnqMBFw
Bjwilson1993 is offline   Reply With Quote
Old 04-25-2016, 01:38 PM   #12
04ScoobyWtf
Scooby Specialist
 
Member#: 287974
Join Date: Jul 2011
Default

Yea theyll work. The thicker you go, the closer to stock cr youll get.
04ScoobyWtf is offline   Reply With Quote
Old 04-25-2016, 09:17 PM   #13
Ryan314
Scooby Guru
 
Member#: 82989
Join Date: Mar 2005
Chapter/Region: SWIC
Location: Arizona
Vehicle:
2002 WRX
Hybrid EJ257

Default

Quote:
Originally Posted by danger1138 View Post
I agree with this method. I machined my heads when i went the hybrid route. It has lasted me 90k and counting but ^ this method right here is another route you can take. If you read thru the forums in regards to hybrid builds you will realize that machining your heads isnt the only method for achieving success.
Running a thicker HG is just a band aid fix to not having the heads machined. You will still have head over hang regardless which is prone to hot spots, which can lead to detonation. I'm not saying there hasn't ever been a successful hybrid build without, however, for the cost of having them done, it's a no brainer and shouldn't be overlooked.
Ryan314 is offline   Reply With Quote
Old 04-25-2016, 10:39 PM   #14
RexWagonWA
Scooby Newbie
 
Member#: 221945
Join Date: Aug 2009
Default Hybrid build

Quote:
Originally Posted by Ryan314 View Post
Running a thicker HG is just a band aid fix to not having the heads machined. You will still have head over hang regardless which is prone to hot spots, which can lead to detonation. I'm not saying there hasn't ever been a successful hybrid build without, however, for the cost of having them done, it's a no brainer and shouldn't be overlooked.
If you do not want to match your 2 ltr. Head to your EJ 257 short block. Buy the JE pistons for the hybrid applications. Have a knowledgable Subaru machine shop work with you. Forget using machine shops that do not have a proven Subaru track record.

GLWYB
RexWagonWA is offline   Reply With Quote
Old 04-25-2016, 11:22 PM   #15
Bjwilson1993
Scooby Newbie
 
Member#: 383734
Join Date: Mar 2014
Chapter/Region: NWIC
Location: Salem, Oregon
Vehicle:
1995 Legacy Outback
Green/ Matte Black

Default

I found a shop to hand match from the HG just 1mm in from it since the motor is bored to 100
Bjwilson1993 is offline   Reply With Quote
Old 04-26-2016, 03:12 PM   #16
FlatironsTuning.com
Former Vendor
 
Member#: 171650
Join Date: Feb 2008
Location: Boulder, Colorado
Default

Quote:
Originally Posted by Bjwilson1993 View Post
Okay so we're going with a forged short block. (Forged rods and Pistons) http://m.ebay.com/itm/272213507269

Going to port and polish the heads with stage 2 cams https://www.rallysportdirect.com/fit...-272-camshafts

and double spring valve springs.

New headers and up pipe. New Downpipe don't know what turbo to get yet ( please give some suggestions based on build)

Front mount intercooler possibly 555cc injectors. And upgraded fuel pump and obviously a healthy tuning.

Any constructive criticism or ideas are greatly appreciated.
With your build, the first thing to consider are your power goals. This will narrow down your turbo selection, and it will help to determine whether some of the other parts are going to be required.

More than likely, you will be happier long term if you go with a larger injector. Specifically a 1000cc injector based on the Bosch EV14 (ID, Cobb, Deatschwerks). Installing them is very straight forward, and won't require rails, etc.

For the cams, and valve springs, again, your power goal, and target RPM redline will help to determine whether you actually need those or not. I'll also say that the dual valve springs may be more complexity than required. you may want to look at a good bee-hive spring in comparison. Remember that typically, the more aggressive the cam, the more you will be sacrificing power in the lower rpm range and gain power in the upper rpm range.

Lastly, you have 3 options to help to compensate for the increased compression and combustion chamber issues of a hybrid. Those are thicker head gaskets, a hybrid piston (JE's as mentioned earlier), and chamber matching the heads. Since you are all ready looking at a built block, you should take a look at the JE pistons. You need forged pistons regardless, and these will take care of both the compression and combustion chamber issues.

I'll mention that the thicker head gaskets are a good option for lower power goals. Also, you want to keep in mind that if your heads have the combustion chamber cracks that the 2.0 heads are prone to, most machine shops will not chamber match them. So that may be an added expense that you want to account for.

I hope that helps, and good luck with your build!
FlatironsTuning.com is offline   Reply With Quote
Old 04-29-2016, 10:02 AM   #17
no694terry
Scooby Specialist
 
Member#: 220816
Join Date: Aug 2009
Location: Pittsburgh PA
Vehicle:
2018 Exotruck

Default

JE makes FSR pistons specifically for this build that doesnt required heads to be machinced, theyre also dished to pick your compression ration. No more expensive than other forged pistons either.

but if your only going to 555 injectors than your power limit isnt goign to be to the point where this is even an issue
no694terry is offline   Reply With Quote
Old 09-13-2016, 12:47 PM   #18
BrianSP95
Scooby Newbie
 
Member#: 453304
Join Date: Aug 2016
Default

Awesome post helped me make my decision.
BrianSP95 is offline   Reply With Quote
Old 09-13-2016, 12:51 PM   #19
Samurai Jack
Scooby Guru
 
Member#: 21145
Join Date: Jul 2002
Chapter/Region: NESIC
Location: Not in my own time
Vehicle:
2002 Enemy of Aku

Default

Quote:
Originally Posted by Bjwilson1993 View Post
Any constructive criticism or ideas are greatly appreciated.
There is a whole thread on "So you want to Build a 2.X Hybrid" or something close to that

Have you read that thread?
Samurai Jack is offline   Reply With Quote
Old 09-13-2016, 01:49 PM   #20
Dave D.
NASIOC Supporter
 
Member#: 130990
Join Date: Nov 2006
Chapter/Region: NWIC
Location: Menzel Lake, WA
Vehicle:
06 Red Ltd.Wagon
Dom 1.5xtr JJ tuned

Default

Quote:
Originally Posted by FlatironsTuning.com View Post
More than likely, you will be happier long term if you go with a larger injector. Specifically a 1000cc injector based on the Bosch EV14 (ID, Cobb, Deatschwerks). Installing them is very straight forward, and won't require rails, etc.
This.
Dave D. is online now   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 02:13 PM.


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.