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Old 12-08-2008, 10:54 PM   #1
cthomasset
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I made a separate thread after reading pretty much every post containing the words "hybrid", "intake", "SRI", and "CAI". I noticed that in 2008 the airbox changed slightly from previous years. The MAF is now integrated into the airbox housing and the accordion pipe from the MAF to the torque box is shaped differently. These things led me to believe that the 2008 may be a little different. Hence, new thread...

First: I purchased an ebay intake with the intent of hacking it up like so many others. I made two cuts on the pipe. One before the 45 Deg bend going to the MAF and the other near the apex of the pipe. Not hot, I needed a 3" coupler that was 3" long and 4" pipe drain coupler (home depot style) at the airbox to make it work. I was not thrilled. It barely fit and seemed way too tight.

I then decided to comb the internets to see what I could find from the Legacy guys. Found that they were more often running a different style of ebay intake which can no longer be found. See it here:



I am not okay with this, all the pictures from the Legacy forum make this intake look like it fits without hacking. So once again I head to the intertubes . I come up with this:

Intake

Bingo! Good price no less with free shipping.

1998-2001 Subaru Impreza - Kool Vue Cold Air Intake

P/N KV4801073K

I recieve it, take everything apart (again) and see whats up. Well, it almost fits perfectly. It just needs to be stretched towards the front of the car slightly. Can do. One hack and done, its probably extended no more than 1". Oh, and, this intake comes with all the extra hose you need. You can see it here:





What else do I need to complete the job?

Auto Parts Store:

2 x 3" silicone coupler. One for the hack, one for the airbox.



8 x Hose clamps



1 x 3/8" vacuum cap for that stupid grommet (why are you there?!?)



Home Depot:

3 x 1/2" - 1/2" brass hose barbs to add some inches to the breather lines.



1 x Hacksaw (to cut the pipe)

1 x Knife (to cut the hose)

1 x Socket set

1 x Screwdriver set

Liquor Store:

6 x Beer of choice for a job well done



Process:
  1. Take everything apart. Loosen hose clamps on the accordion hose and TB. Then remove the 10mm bolts for the torque box. Remove the breather lines. The large house clamps on the intake are 8mm. Remove, remove, remove.
  2. Attach the silicone coupler from TB to the intake pipe. Measure everything up so you know where to cut. If confused...look at my pics.
  3. Assemble the coupler - pipe - coupler - pipe - coupler contraption. Get it all tightened down.
  4. Shove a 1/2" brass barb into that damn grommet. Place Vacuum cap over it.
  5. Measure hose for the breather lines. Use one barb per line. I am referring to the lines that enter the torque box from either side. You can see that this intake has long nipples on both sides near the TB.
  6. The White sensor is fun. Just Get some hose, shove it into the large diameter hose (relatively speaking) coming off the sensor and attach it to the free nipple.
  7. Reconfirm attachment and tighten it all down, again.
  8. Reset ECU. Disconnect negative terminal (10 mm) and hop on the brakes for 60 seconds.
  9. Reconnect neg terminal.
  10. Start car and let it warm up.
  11. Drive the piss out of it.
  12. Enjoy the experience.
  13. Come home and drink beer.

Last edited by cthomasset; 04-06-2009 at 04:05 PM.
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Old 12-08-2008, 11:41 PM   #2
iommichild
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Nice writeup. Do you feel any difference? Has it been on long enough to get any measure of fuel economy at all? Us nonturbos have pretty limited options for intakes, so its cool that you figured all this out!
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Old 12-09-2008, 01:45 PM   #3
cthomasset
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Quote:
Originally Posted by iommichild View Post
Nice writeup. Do you feel any difference? Has it been on long enough to get any measure of fuel economy at all? Us nonturbos have pretty limited options for intakes, so its cool that you figured all this out!
There is a certain difference. I notice it most when in the upper rev range, which is not surprising. But there is more power in every gear even when you are not flogging it. It gets a bit noisy at the top (to be expected, sounds cool though), but cruising at 70mph you can't tell a difference from stock. It only gets noisy when you get on it, otherwise it sounds fairly mundane.

There was a dyno up on the forum somewhere that I saw, showed some good gains if I remember right.

As far as economy goes, I have not had it on there very long. Time will tell, and I should have some numbers over the next few weeks when I get back to a normal commuting schedule.
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Old 12-09-2008, 12:49 AM   #4
RaceFaceXC
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Nice work. looks clean and sound. Do you have the necessary equipment to do some ECU logging?
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Old 12-09-2008, 02:45 PM   #5
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the picture of the intake kit you settled on is missing... link??
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Old 12-09-2008, 06:52 PM   #6
cthomasset
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Quote:
Originally Posted by Battlesnake99 View Post
the picture of the intake kit you settled on is missing... link??

I am at the 10 picture limit for the post. Here it is...from the website linked above.


Last edited by cthomasset; 12-09-2008 at 07:22 PM.
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Old 12-09-2008, 07:08 PM   #7
RaceFaceXC
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have you any way to rescale the MAFv table? I would highly suggest you do this for reliability sake.
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Old 12-09-2008, 07:30 PM   #8
cthomasset
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Quote:
Originally Posted by RaceFaceXC View Post
have you any way to rescale the MAFv table? I would highly suggest you do this for reliability sake.

I have a dashhawk (http://www.dashhawk.com/)...I think it will log ECU parameters. Last time I used it was for boost pressure on my last car.

What to you mean by MAFv rescale exactly?

I thought we only ran into MAF issues on the NA engine when using a cone air filter...
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Old 12-09-2008, 07:38 PM   #9
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its rescaling the MAFv table to be better calibrated for the new intake.


MAF issues have been found on the subaru N/A MAF based engines. The problem has been proven to exist on 05-07's and id bet that the 08 would also have the same problem. BUT, the hybrid intake you have takes care of the MAFv spikes, but does not retain the stock MAFv scaling as being ideal. So a MAFV table rescale is necessary to ensure that your AFR's are what they should be and that the ECU isnt adjusting fuel learning by huge amounts just to try and get it close to target.
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Old 12-09-2008, 07:49 PM   #10
cthomasset
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Quote:
Originally Posted by RaceFaceXC View Post
its rescaling the MAFv table to be better calibrated for the new intake.


MAF issues have been found on the subaru N/A MAF based engines. The problem has been proven to exist on 05-07's and id bet that the 08 would also have the same problem. BUT, the hybrid intake you have takes care of the MAFv spikes, but does not retain the stock MAFv scaling as being ideal. So a MAFV table rescale is necessary to ensure that your AFR's are what they should be and that the ECU isnt adjusting fuel learning by huge amounts just to try and get it close to target.
I see. Well, I don't have anything to rescale the MAF.

However, I do have a dashhawk that could monitor this stuff. Assuming what I have will work, what should I monitor?

Calculated load?
AFR?
MAF values?

I am more of a hardware than software guy, so I am a bit lost in this arena.
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Old 12-09-2008, 10:09 PM   #11
RaceFaceXC
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There is a thread on here that Williaty posted a technique for scaling the MAFv table. Which you could do with the dashhawk, but unless you can actually modify/change the table values (edit the ECU image) then its not going to do you much good. you could find out how far off it is though. Check your A/F learning. i think A/F learning D is the long term learning trend (dont quote me on that) and you want it to be as close to 0 as possible. Mine is rarely over 1% and i have never seen it over 2% since i rescaled. anything over 4-5% is too much in my opinion. If your A/F learning parameters are all whacked out then its safe to say that you need to rescale your MAFv table.
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Old 12-10-2008, 04:33 PM   #12
Battlesnake99
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i still dont see a link...
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Old 12-10-2008, 06:01 PM   #13
RaceFaceXC
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cthomasset - do you have a laptop? and $65 or so? you could solve this problem and many others that may arise, just to scratch the surface.
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Old 12-10-2008, 06:27 PM   #14
cthomasset
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Quote:
Originally Posted by RaceFaceXC View Post
cthomasset - do you have a laptop? and $65 or so? you could solve this problem and many others that may arise, just to scratch the surface.

I will look into it. More of a time issue than a money issue. But I already went this far...
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Old 12-10-2008, 06:41 PM   #15
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k, well if you are thinking about it and have the time, start doing some reading over @ www.romrraider.com keep in mind a huge majority of the users are drivers of forced induction vehicles. But the software works the same no matter what. and its much simpler to tune an N/A motor in my opinion. fewer variables and less dynamic in terms of changes going on with the engine.
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Old 12-10-2008, 07:18 PM   #16
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cthomasset need the link to carry out your beautiful write up!

raceface as a side, doesnt a tactrix cable cost like $180 or something? plus if you want A/F sensor/reader thats another $200...
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Old 12-10-2008, 08:07 PM   #17
RaceFaceXC
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Quote:
Originally Posted by Battlesnake99 View Post
cthomasset need the link to carry out your beautiful write up!

raceface as a side, doesnt a tactrix cable cost like $180 or something? plus if you want A/F sensor/reader thats another $200...
I paid $70 after shipping for the Tactrix openport 1.3 cable. there is a 2.0 cable now, which is more expensive. dont know the price on it, but its not needed for OBD-II based ECU interfaces. Only necessary for the new CAN based ECU's. (08+) and since the new 2.0 cable offers some features that the 1.3 doesn't, i would bet you could find the 1.3 even cheaper than what i paid a year+ ago.

I didnt find any WBO2's with a gauge for less than $300, so i dont know what the cost would be exactly. depends on how the user wants to use it. With a computer or without? the gauge is what costs the most it seems.
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Old 12-10-2008, 08:35 PM   #18
cthomasset
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Quote:
Originally Posted by Battlesnake99 View Post
cthomasset need the link to carry out your beautiful write up!

raceface as a side, doesnt a tactrix cable cost like $180 or something? plus if you want A/F sensor/reader thats another $200...


http://www.autopartswarehouse.com/details/QQSubaruQQImprezaQQKool_VueQQCold_Air_IntakeQQ1998 2001QQKV4801073K.html

Its at the top of the post after the first picture.

Last edited by cthomasset; 12-10-2008 at 09:26 PM.
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Old 12-10-2008, 08:25 PM   #19
Battlesnake99
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actually just found out theyre making a 2005+ 2.5i Cobb Accessport! comign out in February. im stoked.
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Old 12-11-2008, 01:33 PM   #20
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Quote:
Originally Posted by Battlesnake99 View Post
actually just found out theyre making a 2005+ 2.5i Cobb Accessport! comign out in February. im stoked.
WAAAA ????? no way ! gimmie the source of this info !
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Old 12-10-2008, 09:02 PM   #21
Battlesnake99
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i seriously cant see it... i tabbed through the page for all links and nothing came up in your first post... please jsut post it again id really appreciate it
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Old 12-10-2008, 09:24 PM   #22
cthomasset
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Quote:
Originally Posted by Battlesnake99 View Post
i seriously cant see it... i tabbed through the page for all links and nothing came up in your first post... please jsut post it again id really appreciate it
Its posted now, twice. You must be running some type of script/ad block or anti-redirect/phishing software. I can see the links fine, on multiple computers.

www.autopartswarehouse.com

autopartswarehouse.com

Search for 1998-2001 Subaru Impreza - Kool Vue Cold Air Intake

P/N KV4801073K

That should probably be in the first post anyway.

Last edited by cthomasset; 12-10-2008 at 09:32 PM.
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Old 12-10-2008, 09:35 PM   #23
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nevermind

Last edited by AfflxnPB; 12-19-2008 at 12:49 PM.
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Old 12-10-2008, 10:43 PM   #24
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I forgot/went blank and didnt acknowledge that you have an 08, so the tactrix openport 2.0 cable is currently $169. for some reason i kept thinking you have an 06.

Openport 2.0 data cable


I dont think the less expensive openport 1.3 data cable will work for an 08+
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Old 12-10-2008, 10:49 PM   #25
Wagonguy98
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Nice write up, but do you feel that it was worth the money?
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