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Old 07-08-2008, 01:20 PM   #1
Jerry Xu
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Default OBX EL header on 06 07 2.5i

I have an 07 2.5i. Now I see OBX EL header available on ebay again, for years up to 05.
I guess they don't make for 07 year yet. However, I think some of you have actually used this OBX setup on the 06, 07. I am wondering how it fits, and what kind of modifications are needed.
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Old 07-08-2008, 02:13 PM   #2
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I'm guessing it will be like installing the Borlas. You'll need to convert your exhaust to the 05 style to use them.
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Old 07-08-2008, 02:50 PM   #3
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id bolt right on, keep in mind that setup is catless, and than you would either need a 98-05 catback or get a custom one fabbed, or just mod your midpipe already to work with it
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Old 07-08-2008, 03:03 PM   #4
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Jerry, speedyracer still sells the borla replica's on ebay, you just have to send him a message as he has none listed but when I wrote him a few weeks before I got my real borla's, he said he still has them.
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Old 07-08-2008, 05:50 PM   #5
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Quote:
Originally Posted by kero View Post
Jerry, speedyracer still sells the borla replica's on ebay, you just have to send him a message as he has none listed but when I wrote him a few weeks before I got my real borla's, he said he still has them.
Those are UEL though, correct?
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Old 07-08-2008, 05:51 PM   #6
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Quote:
Originally Posted by piker28 View Post
id bolt right on, keep in mind that setup is catless, and than you would either need a 98-05 catback or get a custom one fabbed, or just mod your midpipe already to work with it
Would the OBX clear the newly designed oil tank?
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Old 07-08-2008, 05:57 PM   #7
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ive seen em on a 06 and it had a auto tranny, so it would leave me to believe it would work with you since the auto trans is usually even more of a pain with fitment of those style headers
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Old 07-08-2008, 06:50 PM   #8
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Quote:
Originally Posted by Jerry Xu View Post
Those are UEL though, correct?
Yes they are!
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Old 07-08-2008, 07:37 PM   #9
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dont forget that the obx has a resonator after the collector and not a cat, so if you wanted a cat and/or a happy(happier at least) ECU then a cat should be added. which would require a custom catpipe to attach to the header or a better idea would be to cut out the resonator and weld a cat in place of it. I think the 02 sensors are in a pretty good place for that modification. Either way the OBX header "as is" should bolt up to an 05-98 style midpipe so if you modify it at all, preserve the flange locations, and it should bolt up to an 98-05 catback and you should be golden.
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Old 07-08-2008, 08:21 PM   #10
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Quote:
Originally Posted by kero View Post
Jerry, speedyracer still sells the borla replica's on ebay, you just have to send him a message as he has none listed but when I wrote him a few weeks before I got my real borla's, he said he still has them.
he has them listed again, i just ordered some yesterday. he has 2-3 day shipping also.
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Old 07-08-2008, 10:31 PM   #11
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I don't mind doing a relative simple modification to make it fit. The price is $300 I have some discount on top.

Am I correct that the 07 has 2 cats, one in the EL header, which basically gets eliminated after the obx header installation; another after the O2 sensor (after the resonator pipe?) This one doesn't do anything to the O2 sensor but contribute a bit to the sound generated?

So I will need to do is to cut the obx resonator out, put a HFC in its place and possibly extend the pipe (????) to the next flange (towards the second OEM cat?).
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Old 07-08-2008, 11:33 PM   #12
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Quote:
Originally Posted by Jerry Xu View Post
Would the OBX clear the newly designed oil tank?
Yes. The 06+ sump is smaller than the 05- sump to allow for the new headers. This means you can smack an old style header on the new cars, but to retrofit an old style car, you need both the new header and new sump.
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Old 07-09-2008, 08:06 PM   #13
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Originally Posted by dmab31 View Post
he has them listed again, i just ordered some yesterday. he has 2-3 day shipping also.
Very cool!
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Old 07-09-2008, 10:40 PM   #14
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Very cool!
Why is this a better choice?
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Old 07-09-2008, 11:37 PM   #15
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The EL setup (OBX copy of the MRT header) makes A LOT more torque on the low end than the UEL (borla replicas) do.
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Old 07-10-2008, 05:01 PM   #16
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Quote:
Originally Posted by williaty View Post
The EL setup (OBX copy of the MRT header) makes A LOT more torque on the low end than the UEL (borla replicas) do.
Will this (OBX etc) be more torque still than the OEM (EL) on the 06 07?
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Old 07-10-2008, 05:06 PM   #17
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Quote:
Originally Posted by Jerry Xu View Post
Will this (OBX etc) be more torque still than the OEM (EL) on the 06 07?
One would assume so. There's no direct 06+ vs EL data available but we can do a little bit of dodgy reasoning and come up with an answer. Subaru tells us that the difference between and 05 and 06 engine is about 10hp. Putting on UEL headers to an old-style car has showed bigger gains than that across the entire rev range. Then, a few years later, that same car switched to EL headers and saw another 15-20lbft on the low end. So logic suggests that since the EL showed big gains over a setup that already should have been more powerful than a stock 06+, the EL setup should have more gains on a 06+.

Last edited by williaty; 07-10-2008 at 10:11 PM.
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Old 07-10-2008, 09:39 PM   #18
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That does make sense.

You meant:
"that same car switched to EL headers and saw another 15-20lbft..."
?
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Old 07-10-2008, 10:11 PM   #19
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Yes, that's what I meant. I corrected the post.
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Old 07-11-2008, 11:40 AM   #20
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williaty know his stuff^^^!!!!so does anyone make headers for 06-07?
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Old 07-11-2008, 12:37 PM   #21
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^^ Not sure but borla UEL's and or replica's fit out cars, but we have to change everthing from the header back once installed.
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Old 07-11-2008, 02:10 PM   #22
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kero has it. All the headers are 05- fitment. You either have to convert entirely to an 05- exhaust setup or get someone to custom fab your new 05- header to the rest of your 06+ exhaust system.
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Old 07-11-2008, 04:09 PM   #23
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^^After reading a ton of threads on this stuff and asking a million questions, it's nice to be able to help others and of course WILLIATY has helped me quite a bit as well
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Old 07-11-2008, 04:22 PM   #24
Jerry Xu
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For the modification (not to change the whole setup to 05 exhaust), see if I get this right.

1) Get the OBX for the 05 cars. Put the header on direct fit. But,
2) Cut out the resonator on the OBX piece.
3) Put in its place a HFC (if so desired). Weld using the OBX flanges from resonator.
4) Adjust angle and distance so one flange fit the header, the other to next flange down stream on the 07 setup.

Step "4)" is the part I am not totally clear...

http://www.tuningdepot.com/ebay/images/H10798(3).jpg
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Old 07-11-2008, 04:25 PM   #25
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Here's what I'd do:

1) Take the stock header and cat section off
2) Put the OBX header on
3) Disconnect the MAF sensor so the car goes into limp mode
4) Drive slowly to an exhaust shop
5) Get them to put the car on the lift
6) Point to the header and then to the existing midpipe and say "Connect that to that with this in the middle" while handing them a universal HFC.
7) Grab the O2 sensors and say "oh, and these need to go in there somehow too"
8) ????
9) Profit!
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