How to install Unequal Length headers on your 2.5i

ZeppelinPie792 · 02-09-2008, 07:55 PM

As we all know, our 2.5i's come with the dreaded equal length headers. Some like them for the rumored performance gain over unequal length headers, and others hate them for their sound. I am in the latter category. Just know that whatever you do, either one will be better than your stock "exhaust manifold" because you will most likely be getting rid of a catalytic converter.

So if you are balls out performance, go ahead and get yourself some OBX equal length headers that supposedly bolt right up. But if you want that boxer rumble, you will most likely need unequal length headers.

Step 1: Deciding if you really even want to go through with it:

This will be expensive, and it will be time consuming. It may also be quite aggravating. You will have to replace your entire exhaust, and get an extension cable for your rear O2 sensor. I am 95% sure you can not use any stock part, and you MUST replace everything (except your O2 sensors). Let me do a quick rundown on the estimated prices without shipping:

Cheap
Headers: Borla Replicas ($200)
Cat pipe: Used 2.5RS Catpipe ($75)
Cat Back: Generic eBay Cat Back ($300)
O2 ext.: DIY Soldering ($5?)
_____________________
$580

Expensive
Headers: Borlas ($300)
Cat Pipe: High Flow Cat ($360)
Cat Back: Name Brand Cat Back ($550)
O2 ext.: Rear O2 Sensor Extension ($32)
___________________
$1242

So as you can see, it will be quite expensive. If you are willing to pay that much money, then keep reading.

Just as a side note, I got the prices for the cheap route from things for sale here and eBay. You may not have to extend the rear O2 sensor if it is a 2.5RS cat pipe, but I am not too sure.

The prices from the Expensive route are mostly from boxer4racing.com I mainly used things on here, with the exception of the Borlas.

Step two: Picking out the right parts:

In this section I will offer suggestions for which parts you will need. You want to be sure you have all of your parts before putting your new exhaust on, or it will more than likely not fit.

-Headers:

There are two big options you have here...

1) You can go to eBay and get yourself a pair of Borla Unequal Length Replica Headers. This tends to save you about $100. Most people do this since they claim the quality is as good as, if not better, than Borla's headers.

2) You may also get a pair of Borla headers. A place you can order them from is http://www.boxer4racing.com/ but just know that you will have to phone order. Beware of the earlier generation Borlas, as they are prone to cracking. They are covered by a million mile warranty, which goes to a joke I have heard, "Just get yourself two things of Borla headers. When one cracks, you put number two on while you send the first ones in for warranty work. When number one gets back, number two should be ready to go".

WARNING: IF YOU DO THIS, DO NOT PAY ATTENTION TO ANY OF THIS HOW TO: The third (and unorthodox) option of this is to get a WRX or STi header and modify it to work on our 2.5i's. Here is a link of a forumite named Vizzionz that had done this to his 2.5i http://forums.nasioc.com/forums/show....php?t=1420502

-Cat Pipe:

There are 3 general options here.

1) The cheap thing to do here is to just buy a used 2.5RS cat pipe from an 02-05 RS. This should work fine, and I do not think you have to get a rear O2 extension if you go down this path. (Please message me if I am wrong here)

2) But, if you are like me, you want to get something that you do not plan on replacing. This means a high flow catalytic converter. I got the Stromung high flow cat from boxer4racing.com. The other main choice for high flow cats from my research is the Random High Flow Cat. If you get a high flow cat, under my understanding, you will have to re-locate your female connectors in your engine bay, and get a 24" or so extension for the rear O2 sensor. Also, High Flow cats tend to be quite loud, although they give you better fuel economy and increased horsepower.

3) You can also get a track pipe. This is the cat pipe without the actual catalytic converter. It is only recommended that you do this if your county has no emissions testing (and if you do not really care about the environment).

-Catback:

Not much to say here. Just a mid pipe and tail pipe. One catback that I see recommended a lot is a Stromung cat back. Really, anything designed for an 02 to 05 model will work. The optimal size is 2.25"-2.5" though.

-O2 sensor extension:

Well, I am not too sure about regular 2.5RS cat pipes, but if you get a high flow cat, you will have to get your rear O2 sensor extended. You can either buy an extension for $32, or go in, chop up your wire, and solder it all yourself. I would provide a link on how to splice wires yourself, but I do not remember exactly where I saw a post about it. If someone PM's me this, I will replace this sentence with it.

If you want to just buy an extension, you will need a 24" one from this place:
http://www.casperselectronics.com/mm...gory_Code=SUBU

-O2 Sensor Spacer:

Some people's check engine lights go off, so you may have to get this O2 sensor spacer at http://www.rallitek.com/rao2sesp.html or do a mechanical fix. Here are the steps for the mechanical fix, as from a previous forumite:

Go to autoparts store and buy "Help!" brand spark plug anti-foulers. They look like threaded O2 bungs and come in a red package. You need one each of part number 42002 and 42009.

Take the one with the crush-washer on it (#2) and drill the center out with a 1/2" drill bit (clamp it in a vise and go at it - it's soft metal so the drilling is easy).

screw the #2 together with #1 and put them in between your rear O2 sensor and the bung on the cat. You'll never get the P0420 CEL after that.

My CEL never went off after everything was hooked up, so I believe the extension chord should be fine.

Step three: Putting everything on:

This is pretty much self explanatory. You securely lift up your car, take everything old off, and put your new things on. You will want to unscrew your O2 sensors and put those in your new cat pipe. You may want to use some kind of lubricant to get your exhaust out of the rubber hangers, and maybe even have someone else help you with getting the bolts out. If you have a torque wrench, I think you need to torque it up to 34 ft/lbs. If I am wrong, please message me so I can correct this.

If you do not re-locate your female connectors, this is what will happen to your cables:

(The rear O2 sensor cable is actually not even long enough to make it to the engine bay)

That being said, you will have to re-locate the female connector to the back of your engine bay instead of where it already is. To do this, unless you are extremely dexterous, you will most likely have to unbolt this thing:

(Sorry for the bad picture, but I could not get a good one with the air intake tube in the way. Just know it is under this weird shape

With that off, it should go right through. I actually had to take out the accordion tube in my air intake to get to it. With the 24" rear O2 cable extension on, it should fit right in. I also securely tied them down afterwards.

If your check engine light goes off, you may have to put on the rallitek O2 sensor spacer, or do the mechanical fix. The O2 sensor spacer should just screw in. See the bottom of section two for the mechanical fix. Once again, my CEL did not go off after I had everything hooked up, and I have heard that it shouldn't with the extension cable.

Step 4: Enjoy!

If you get this to all work, congratulations, your car now sounds like a Subaru. My brother always ridiculed me for my car sounding like a Honda when I had only my cat back on. Now, he actually likes the sound. If any of you guys experienced anything like that, it will happen no longer! Now people will ask you if you are packing a V8, or get your car confused for a WRX or STi.

Common Misconceptions/Concerns:

-Some people have said the headers will not fit due to it not clearing the oil pan. Mine are snug as the headers in a bugeye (bad joke, I know). Here is the best picture I could take to prove it wrong:

-If you think the oil filter will be hard to get out, it will be just about the same as the stock headers. I have not had to change my oil at the time of writing this, so I can not tell you the real level of difficulty. It looks like it won't be too hard. Here is a picture to show you about it:

Videos:

If you would like me to post links to your videos here, just let me know. It is always nice seeing the difference these make.

Me:
Before, revving: http://www.youtube.com/watch?v=2D0QZXzM5Go
After, revving (although it does not do it justice IMO): http://www.youtube.com/watch?v=22IObVoul0Y
After, driving: http://www.youtube.com/watch?v=SkvETX5ISgY

Conclusion:

If you want to see my path down doing this, I have a long thread about it here: http://forums.nasioc.com/forums/show....php?t=1424157
But be warned, half of it is just me replying to things. I will try not to do that on this thread.

If you have any comments/concerns/questions/etc or if you see anything in my how-to that needs to be changed, please feel free to PM, IM, or email me.

* Registered users of the site do not see these ads.

GlobalWaste · 02-09-2008, 07:58 PM

A cheaper method is modifying a set of WRX headers to fit

Involves drilling a new O2 sensor bung, modifying a flange and extending a wire but it works pretty well if you ask the right people.

Nice writeup though

RaceFaceXC · 02-09-2008, 09:39 PM

yeah, im sure this will help countless impreza owners for many years. good job. I have some EL headers and plan on doing a writeup for those, but it will be pretty much the same as this so maybe i wont bother. i do have a ? for you though, if you dont want to relocate your O2 sensor plugs in the engine bay, will 2 O2 extensions work?

Victor1620 · 02-09-2008, 09:53 PM

"As we all know, our 2.5i's come with the dreaded equal length headers. Some like them for the rumored performance gain over unequal length headers..."

rumored?

RaceFaceXC · 02-09-2008, 09:59 PM

Quote:

Originally Posted by Victor1620

"As we all know, our 2.5i's come with the dreaded equal length headers. Some like them for the rumored performance gain over unequal length headers..."

rumored?

Yeah, its a def gain due to the EL headers, i was going to say something too but i know what he meant and didnt want to be a douche and pick him off on that. Besides, i think about 95% of EL header equipped impreza owners that want to do headers will go with UEL's for the sound so the thread is very justified.

skribblez32 · 02-09-2008, 10:11 PM

great write up man. glad everything worked out for you. that nur-spec sounds mean as hell. i might have to go with a high flow cat now lol. ur nur-spec is 2.5" right?

this should be stickied for people wanting to do this in the future. we all know how many threads have been started about this topic.

ZeppelinPie792 · 02-09-2008, 10:18 PM

Quote:

Originally Posted by skribblez32

great write up man. glad everything worked out for you. that nur-spec sounds mean as hell. i might have to go with a high flow cat now lol. ur nur-spec is 2.5" right?

this should be stickied for people wanting to do this in the future. we all know how many threads have been started about this topic.

I believe it is a full 3", and it tapers down to 2.5". I know it is way too big, but oh well, I like the sound.

banjabi · 02-09-2008, 11:21 PM

well written. good lookin out bro.

Sylon · 02-10-2008, 08:39 AM

What about gaskets? They all need to be replaced too right? Great write up dude, this is awesome.

ZeppelinPie792 · 02-10-2008, 02:48 PM

Quote:

Originally Posted by Sylon

What about gaskets? They all need to be replaced too right? Great write up dude, this is awesome.

From my understanding, it is always a good idea to replace your gaskets when you replace anything on your exhaust. Most pieces should come with gaskets, though.

dan13 · 02-10-2008, 02:52 PM

I have a full 3" and have no problems with it. Top end is were it pulls through but im more interested in the tone. Thanks for the write up zep!

Sylon · 02-10-2008, 04:52 PM

Quote:

Originally Posted by ZeppelinPie792

From my understanding, it is always a good idea to replace your gaskets when you replace anything on your exhaust. Most pieces should come with gaskets, though.

Thats what I figured. I just thought I would mention it for the simpletons out there, lol.

dedrooster · 02-10-2008, 05:08 PM

I just stumbled on this thread after doing a quick search while taking off my cracked Borla header, and it's an interesting read. What are you guys doing with all of your EL parts? Selling them real cheap?

Is the axle-back/muffler different from earlier (un-equal length) models on the 06/07?

ZeppelinPie792 · 02-10-2008, 06:49 PM

Quote:

Originally Posted by dedrooster

I just stumbled on this thread after doing a quick search while taking off my cracked Borla header, and it's an interesting read. What are you guys doing with all of your EL parts? Selling them real cheap?

Is the axle-back/muffler different from earlier (un-equal length) models on the 06/07?

Who would even want that?

Anyways, I always keep my stock stuff so I can revert back if needed for warranty work. I believe the muffler itself is different (see the next picture), but others will bolt up for the axle back I THINK

dedrooster · 02-10-2008, 08:07 PM

Quote:

Originally Posted by ZeppelinPie792

Who would even want that?

Some people like EL

Me? I love the 'Subaru rumble,' but it isn't important enough to me to keep me from ditching it if I could possibly eek out another 5hp on the cheap.

It does look like it might make changing the oil filter a messy proposition.

Oh, and I see why you "have to" change the axle-back on an '07 now.

/hijack

guciodog11 · 02-10-2008, 08:20 PM

$580 ROFL

get this
http://cgi.ebay.com/ebaymotors/Subar...spagenameZWDVW
and this
http://cgi.ebay.com/ebaymotors/Catba...spagenameZWDVW

use your stock cat for a total of 273........

ZeppelinPie792 · 02-10-2008, 08:36 PM

Quote:

Originally Posted by guciodog11

$580 ROFL

get this
http://cgi.ebay.com/ebaymotors/Subaru-Impreza-WRX-02-03-04-07-Exhaust-Header-Manifold_W0QQcmdZViewItemQQcategoryZ33631QQihZ001Q QitemZ110223207471QQrdZ1QQsspagenameZWDVW

I have never heard or seen anything about this. My thinking was "If there were UEL headers for a 2.5i, everyone would know about them"

RaceFaceXC · 02-10-2008, 08:57 PM

i hate how they say they will fit all those years but dont say that you need to change other stuff too. not cool. irresponsible merchant.

guciodog11 · 02-10-2008, 09:04 PM

Quote:

Originally Posted by ZeppelinPie792

I have never heard or seen anything about this. My thinking was "If there were UEL headers for a 2.5i, everyone would know about them"

think of them another way. Those are headers for a turbo, just without an up-pipe, not headers made for a 2.5i

90% sure they will fit without any problems, the biggest one is finding another location for the 2nd o2 sensor, it being on the up-pipe on turbo subies. we prob have to put it in right before the stock cat.

it took me 2 mins to find those, had no idea the problems you guys were going through looking for headers for the 2.5 lol

skribblez32 · 02-10-2008, 10:03 PM

Quote:

Originally Posted by guciodog11

$580 ROFL

get this
http://cgi.ebay.com/ebaymotors/Subar...spagenameZWDVW
and this
http://cgi.ebay.com/ebaymotors/Catba...spagenameZWDVW

use your stock cat for a total of 273........

You know those are WRX parts you listed? Buying those and getting them "modified" to fit a 2.5i will take some money and time. And you can't use your stock cat in a 2.5i because the cat is integrated with the header. Sorry to burst your bubble.

Counterfit · 02-10-2008, 10:08 PM

Quote:

Originally Posted by ZeppelinPie792

Who would even want that?

Mandrel bent and a 4-1 collector.

Quote:

Anyways, I always keep my stock stuff so I can revert back if needed for warranty work.

Warranty fraud ftw?

guciodog11 · 02-11-2008, 12:26 AM

Quote:

Originally Posted by skribblez32

You know those are WRX parts you listed? Buying those and getting them "modified" to fit a 2.5i will take some money and time. And you can't use your stock cat in a 2.5i because the cat is integrated with the header. Sorry to burst your bubble.

The two cats are totally separate. look at the picture posted above. you unbolt the header from the stock 2nd cat and pipe (no idea what its called) and connect it to the header i posted. The only problem is tapping a hole for the 2nd o2 sensor. the only thing different between our cars and the wrx or sti is that they have up-pipes, turbos and down pipes. all we have to do is use stock cat and the pipe to bridge that gap and we're good. Im not saying its a bolt on job, but pretty damn close lol. all wrx or sti headers are direct bolt ons, its the up-pipe that causes problems. no up-pipe, no problems

'93Impreza1.8T · 02-11-2008, 01:02 AM

here are some uel headers on ebay that i found they cost US $239.99 + $22.91 for shipping

http://cgi.ebay.com/ebaymotors/Subar...QQcmdZViewItem

skribblez32 · 02-11-2008, 01:52 AM

Quote:

Originally Posted by guciodog11

The two cats are totally separate. look at the picture posted above. you unbolt the header from the stock 2nd cat and pipe (no idea what its called) and connect it to the header i posted. The only problem is tapping a hole for the 2nd o2 sensor. the only thing different between our cars and the wrx or sti is that they have up-pipes, turbos and down pipes. all we have to do is use stock cat and the pipe to bridge that gap and we're good. Im not saying its a bolt on job, but pretty damn close lol. all wrx or sti headers are direct bolt ons, its the up-pipe that causes problems. no up-pipe, no problems

Can you please stop posting incorrect information.

The 2nd "cat" that you're talking about is a resonator. It is part of the mid-pipe of the car. There are cats intergrated in the header, not the mid-pipe.

If you're going to use that resonator, it's going to be like a track-pipe. Which will probably get you a CEL if you don't mod the O2 sensors.

The STi and WRX headers "bolt" up to our engines because it's for a 2.5 dual port block. That's where the similarities end. The exhaust routing is totally different.

PA-Outback2000 · 02-11-2008, 03:56 AM

i would suggest borla-random tech-stromung for exhaust mods. chack boxer4racing.com for stromung and sam at xcceleration.com for all other needs and any questions. they also have a CEL fix that really works. they have had experience with the setup i mentioned and have had 95% success without CEL. this includes the setup above and the CEL fix. once this fix is on, there should be no CEL.

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02-09-2008, 07:55 PM	#1
ZeppelinPie792 Scooby Newbie Member#: 160287 Join Date: Sep 2007 Chapter/Region: TXIC Location: Around Austin, TX Vehicle: 2007 Impreza 2.5i SE Newport Pearl Blue	How to install Unequal Length headers on your 2.5i As we all know, our 2.5i's come with the dreaded equal length headers. Some like them for the rumored performance gain over unequal length headers, and others hate them for their sound. I am in the latter category. Just know that whatever you do, either one will be better than your stock "exhaust manifold" because you will most likely be getting rid of a catalytic converter. So if you are balls out performance, go ahead and get yourself some OBX equal length headers that supposedly bolt right up. But if you want that boxer rumble, you will most likely need unequal length headers. Step 1: Deciding if you really even want to go through with it: This will be expensive, and it will be time consuming. It may also be quite aggravating. You will have to replace your entire exhaust, and get an extension cable for your rear O2 sensor. I am 95% sure you can not use any stock part, and you MUST replace everything (except your O2 sensors). Let me do a quick rundown on the estimated prices without shipping: Cheap Headers: Borla Replicas ($200) Cat pipe: Used 2.5RS Catpipe ($75) Cat Back: Generic eBay Cat Back ($300) O2 ext.: DIY Soldering ($5?) _____________________ $580 Expensive Headers: Borlas ($300) Cat Pipe: High Flow Cat ($360) Cat Back: Name Brand Cat Back ($550) O2 ext.: Rear O2 Sensor Extension ($32) ___________________ $1242 So as you can see, it will be quite expensive. If you are willing to pay that much money, then keep reading. Just as a side note, I got the prices for the cheap route from things for sale here and eBay. You may not have to extend the rear O2 sensor if it is a 2.5RS cat pipe, but I am not too sure. The prices from the Expensive route are mostly from boxer4racing.com I mainly used things on here, with the exception of the Borlas. Step two: Picking out the right parts: In this section I will offer suggestions for which parts you will need. You want to be sure you have all of your parts before putting your new exhaust on, or it will more than likely not fit. -Headers: There are two big options you have here... 1) You can go to eBay and get yourself a pair of Borla Unequal Length Replica Headers. This tends to save you about $100. Most people do this since they claim the quality is as good as, if not better, than Borla's headers. 2) You may also get a pair of Borla headers. A place you can order them from is http://www.boxer4racing.com/ but just know that you will have to phone order. Beware of the earlier generation Borlas, as they are prone to cracking. They are covered by a million mile warranty, which goes to a joke I have heard, "Just get yourself two things of Borla headers. When one cracks, you put number two on while you send the first ones in for warranty work. When number one gets back, number two should be ready to go". *WARNING: IF YOU DO THIS, DO NOT PAY ATTENTION TO ANY OF THIS HOW TO:* The third (and unorthodox) option of this is to get a WRX or STi header and modify it to work on our 2.5i's. Here is a link of a forumite named Vizzionz that had done this to his 2.5i http://forums.nasioc.com/forums/show....php?t=1420502 -Cat Pipe: There are 3 general options here. 1) The cheap thing to do here is to just buy a used 2.5RS cat pipe from an 02-05 RS. This should work fine, and I do not think you have to get a rear O2 extension if you go down this path. (Please message me if I am wrong here) 2) But, if you are like me, you want to get something that you do not plan on replacing. This means a high flow catalytic converter. I got the Stromung high flow cat from boxer4racing.com. The other main choice for high flow cats from my research is the Random High Flow Cat. If you get a high flow cat, under my understanding, you will have to re-locate your female connectors in your engine bay, and get a 24" or so extension for the rear O2 sensor. Also, High Flow cats tend to be quite loud, although they give you better fuel economy and increased horsepower. 3) You can also get a track pipe. This is the cat pipe without the actual catalytic converter. It is only recommended that you do this if your county has no emissions testing (and if you do not really care about the environment). -Catback: Not much to say here. Just a mid pipe and tail pipe. One catback that I see recommended a lot is a Stromung cat back. Really, anything designed for an 02 to 05 model will work. The optimal size is 2.25"-2.5" though. -O2 sensor extension: Well, I am not too sure about regular 2.5RS cat pipes, but if you get a high flow cat, you will have to get your rear O2 sensor extended. You can either buy an extension for $32, or go in, chop up your wire, and solder it all yourself. I would provide a link on how to splice wires yourself, but I do not remember exactly where I saw a post about it. If someone PM's me this, I will replace this sentence with it. If you want to just buy an extension, you will need a 24" one from this place: http://www.casperselectronics.com/mm...gory_Code=SUBU -O2 Sensor Spacer: Some people's check engine lights go off, so you may have to get this O2 sensor spacer at http://www.rallitek.com/rao2sesp.html or do a mechanical fix. Here are the steps for the mechanical fix, as from a previous forumite: Go to autoparts store and buy "Help!" brand spark plug anti-foulers. They look like threaded O2 bungs and come in a red package. You need one each of part number 42002 and 42009. Take the one with the crush-washer on it (#2) and drill the center out with a 1/2" drill bit (clamp it in a vise and go at it - it's soft metal so the drilling is easy). screw the #2 together with #1 and put them in between your rear O2 sensor and the bung on the cat. You'll never get the P0420 CEL after that. My CEL never went off after everything was hooked up, so I believe the extension chord should be fine. Step three: Putting everything on: This is pretty much self explanatory. You securely lift up your car, take everything old off, and put your new things on. You will want to unscrew your O2 sensors and put those in your new cat pipe. You may want to use some kind of lubricant to get your exhaust out of the rubber hangers, and maybe even have someone else help you with getting the bolts out. If you have a torque wrench, I think you need to torque it up to 34 ft/lbs. If I am wrong, please message me so I can correct this. If you do not re-locate your female connectors, this is what will happen to your cables: (The rear O2 sensor cable is actually not even long enough to make it to the engine bay) That being said, you will have to re-locate the female connector to the back of your engine bay instead of where it already is. To do this, unless you are extremely dexterous, you will most likely have to unbolt this thing: (Sorry for the bad picture, but I could not get a good one with the air intake tube in the way. Just know it is under this weird shape With that off, it should go right through. I actually had to take out the accordion tube in my air intake to get to it. With the 24" rear O2 cable extension on, it should fit right in. I also securely tied them down afterwards. If your check engine light goes off, you may have to put on the rallitek O2 sensor spacer, or do the mechanical fix. The O2 sensor spacer should just screw in. See the bottom of section two for the mechanical fix. Once again, my CEL did not go off after I had everything hooked up, and I have heard that it shouldn't with the extension cable. Step 4: Enjoy! If you get this to all work, congratulations, your car now sounds like a Subaru. My brother always ridiculed me for my car sounding like a Honda when I had only my cat back on. Now, he actually likes the sound. If any of you guys experienced anything like that, it will happen no longer! Now people will ask you if you are packing a V8, or get your car confused for a WRX or STi. Common Misconceptions/Concerns: -Some people have said the headers will not fit due to it not clearing the oil pan. Mine are snug as the headers in a bugeye (bad joke, I know). Here is the best picture I could take to prove it wrong: -If you think the oil filter will be hard to get out, it will be just about the same as the stock headers. I have not had to change my oil at the time of writing this, so I can not tell you the real level of difficulty. It looks like it won't be too hard. Here is a picture to show you about it: Videos: If you would like me to post links to your videos here, just let me know. It is always nice seeing the difference these make. Me: Before, revving: http://www.youtube.com/watch?v=2D0QZXzM5Go After, revving (although it does not do it justice IMO): http://www.youtube.com/watch?v=22IObVoul0Y After, driving: http://www.youtube.com/watch?v=SkvETX5ISgY Conclusion: If you want to see my path down doing this, I have a long thread about it here: http://forums.nasioc.com/forums/show....php?t=1424157 But be warned, half of it is just me replying to things. I will try not to do that on this thread. If you have any comments/concerns/questions/etc or if you see anything in my how-to that needs to be changed, please feel free to PM, IM, or email me. * Registered users of the site do not see these ads. Last edited by ZeppelinPie792; 02-18-2008 at 05:04 PM.

02-09-2008, 07:58 PM	#2
GlobalWaste * Banned * Member#: 74792 Join Date: Nov 2004 Chapter/Region: VIC	A cheaper method is modifying a set of WRX headers to fit Involves drilling a new O2 sensor bung, modifying a flange and extending a wire but it works pretty well if you ask the right people. Nice writeup though

02-09-2008, 09:39 PM	#3
RaceFaceXC Scooby Specialist Member#: 165749 Join Date: Dec 2007 Chapter/Region: South East Location: stupid Florida Vehicle: 2007 No YELLING on the bus!	yeah, im sure this will help countless impreza owners for many years. good job. I have some EL headers and plan on doing a writeup for those, but it will be pretty much the same as this so maybe i wont bother. i do have a ? for you though, if you dont want to relocate your O2 sensor plugs in the engine bay, will 2 O2 extensions work?

02-09-2008, 09:53 PM	#4
Victor1620 Scooby Newbie Member#: 146001 Join Date: Apr 2007 Chapter/Region: RMIC Location: New Kolob, U.S.A. Vehicle: '96 Impreza L 559 Red	"As we all know, our 2.5i's come with the dreaded equal length headers. Some like them for the rumored performance gain over unequal length headers..." rumored?

02-09-2008, 10:11 PM	#6
skribblez32 Scooby Specialist Member#: 120609 Join Date: Jul 2006 Chapter/Region: TXIC Location: Austin, TX Vehicle: 2006 2.5i CGM	great write up man. glad everything worked out for you. that nur-spec sounds mean as hell. i might have to go with a high flow cat now lol. ur nur-spec is 2.5" right? this should be stickied for people wanting to do this in the future. we all know how many threads have been started about this topic.

02-09-2008, 11:21 PM	#8
banjabi Scooby Specialist Member#: 119385 Join Date: Jul 2006 Chapter/Region: E. Canada Location: Toronto Vehicle: GDA	well written. good lookin out bro.

02-10-2008, 08:39 AM	#9
Sylon Scooby Specialist Member#: 109000 Join Date: Mar 2006 Chapter/Region: International Location: The land of the Nurburgring Vehicle: 2006 Impreza 2.5i Obsidian Black Pearl	What about gaskets? They all need to be replaced too right? Great write up dude, this is awesome.

02-10-2008, 02:52 PM	#11
dan13 Scooby Specialist Member#: 157726 Join Date: Aug 2007 Chapter/Region: MWSOC Location: Chicago-ish Vehicle: hunk of metal	I have a full 3" and have no problems with it. Top end is were it pulls through but im more interested in the tone. Thanks for the write up zep!

02-10-2008, 05:08 PM	#13
dedrooster Scooby Newbie Member#: 32278 Join Date: Jan 2003 Chapter/Region: South East Location: Raleigh, NC Vehicle: 2000 2.5RS SRP Sedan MB 190E 2.3-16v	I just stumbled on this thread after doing a quick search while taking off my cracked Borla header, and it's an interesting read. What are you guys doing with all of your EL parts? Selling them real cheap? Is the axle-back/muffler different from earlier (un-equal length) models on the 06/07?

02-10-2008, 08:20 PM	#16
guciodog11 Scooby Newbie Member#: 160264 Join Date: Sep 2007 Chapter/Region: Tri-State Location: S.I, NY Vehicle: 95 20G'd EJ255 GC8	$580 ROFL get this http://cgi.ebay.com/ebaymotors/Subar...spagenameZWDVW and this http://cgi.ebay.com/ebaymotors/Catba...spagenameZWDVW use your stock cat for a total of 273........

02-10-2008, 08:57 PM	#18
RaceFaceXC Scooby Specialist Member#: 165749 Join Date: Dec 2007 Chapter/Region: South East Location: stupid Florida Vehicle: 2007 No YELLING on the bus!	i hate how they say they will fit all those years but dont say that you need to change other stuff too. not cool. irresponsible merchant.

02-11-2008, 01:02 AM	#23
'93Impreza1.8T Scooby Newbie Member#: 171092 Join Date: Feb 2008 Chapter/Region: TXIC Location: Count Down City 2-1-0 SATX Vehicle: 1993 Impreza 1.8T Black	here are some uel headers on ebay that i found they cost US $239.99 + $22.91 for shipping http://cgi.ebay.com/ebaymotors/Subar...QQcmdZViewItem

02-11-2008, 03:56 AM	#25
PA-Outback2000 Scooby Specialist Member#: 161832 Join Date: Oct 2007 Chapter/Region: Tri-State Location: PA Vehicle: 2000 Outback Limited Black	i would suggest borla-random tech-stromung for exhaust mods. chack boxer4racing.com for stromung and sam at xcceleration.com for all other needs and any questions. they also have a CEL fix that really works. they have had experience with the setup i mentioned and have had 95% success without CEL. this includes the setup above and the CEL fix. once this fix is on, there should be no CEL.