Subaru WRX Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
17 Posts
Discussion Starter · #1 · (Edited)
Does anyone know if the 04 sti uppipe will fit on the WRXs? I have saved up some subaru bucks and want to see if i can go to the dealerships parts dept. and buy the sti uppipe.
 

·
Moderating on the run!
Joined
·
7,322 Posts
c1k said:
Does anyone know if the 04 sti uppipe will fit on the WRXs? I have saved up some subaru bucks and want to see if i can go to the dealerships parts dept. and buy the sti uppipe.
Yes and ofcourse they are catless- don't know what they run at the dealerships. Post when you find out as guys are having to pay close to $300 from the vendors for new ones.
 

·
Registered
Joined
·
17 Posts
Discussion Starter · #3 ·
They guy in the parts department tells me that he can order it for $340. Part #44104FE090. He gave gave me a exhaust diagram from which i identiy the uppipe and verfiy that that is what im looking for and a list of all the exhast pieces and part numbers which i can post if anyone is interested. However something that makes me curious is that the diagram shows the uppipe with a EGT bung which seems like this may be the wrong piece unless this is a generic printout, which maybe the case since he only gave it to me for me to verify what i wanted. I was under the impression that the sti uppipe did not contain an EGT bung.
 

·
Registered
Joined
·
2,039 Posts
$340 for an STi uppipe!! What is so special about it? Does it off more gains than say a TurboXS or Godspeed uppipe.
 

·
Registered
Joined
·
17 Posts
Discussion Starter · #5 ·
The only reason I want to get it over anything else is because I have a credit card that gives me coupons that I can use at subaru dealerships. So if i use the coupons its no cash out of my pocket and i would be willing to pay a high price with them.
 

·
Moderating on the run!
Joined
·
7,322 Posts
The JDM ones don't have a bung, my guess would either would the USDM. No need for one-it was there strictly to moniter the cat for a catostrphic failure.

What makes the STi piece nice over many others is that it has proven less prone to leak- no doubt due to the flex piece built into it. The piece also comes w/ heat shields intact- a nice touch to reduce underhood temps and keep the air flowing. There is also no bung, so no probe to back (another source for leaks. Also looks oe.

I got mine a long time ago when there was a lot of used JDM ones around- got it for $100 and it was Jet Hot coated to boot.

You'll need to get the resistor (do a search) to keep cels at bay- the resisitor costs all of $1.

Big Sky
 

·
Registered
Joined
·
42 Posts
please correct me if I am wrong, but wouldn't you want a bung in the uppipe so that you can mount an EGT sensor, as I know the temperature sensed will be slightly lower than a stock uppipe, but I would have thought that it would be good to retain an EGT sensor so it can detect and protect from high egt situations, for instance when your tuner over tweaks some of your ecu settings which may cause a lean condition and high egt's ?
 

·
Registered
Joined
·
1,329 Posts
Version 7 is what the bug eyes are (USA 02/03), Version 8 is what the snow shovel hood scoop cars are (USA 04). Their is no need for the egt probe in the uppipe, like big sky said its only to make sure the cat didn't burn up into the turbo. Hundereds of people are using the STI uppipe and not to mention hundereds of others running other uppipes without the egt sensor, I haven't heard of any of those burning up a cat into their turbo :) Its fine, don't worry about it.
 

·
Moderating on the run!
Joined
·
7,322 Posts
Ludecrous said:
please correct me if I am wrong, but wouldn't you want a bung in the uppipe so that you can mount an EGT sensor, as I know the temperature sensed will be slightly lower than a stock uppipe, but I would have thought that it would be good to retain an EGT sensor so it can detect and protect from high egt situations, for instance when your tuner over tweaks some of your ecu settings which may cause a lean condition and high egt's ?
If your going to mount an EGT probe, it should be where it is most useful- nearest the source in the exhaust manifold.

If one really wants one in the uppipe- it costs very little to have bung welded in.

Big Sky
 

·
Moderating on the run!
Joined
·
7,322 Posts
Ludecrous said:
please correct me if I am wrong, but wouldn't you want a bung in the uppipe so that you can mount an EGT sensor, as I know the temperature sensed will be slightly lower than a stock uppipe, but I would have thought that it would be good to retain an EGT sensor so it can detect and protect from high egt situations, for instance when your tuner over tweaks some of your ecu settings which may cause a lean condition and high egt's ?
If your going to mount an EGT probe, it should be where it is most useful- nearest the source in the exhaust manifold.

If one really wants one in the uppipe- it costs very little to have bung welded in.

Big Sky
 

·
Registered
Joined
·
42 Posts
cool, I was just thinking there must be a valid reason..i.e..why the EGT probe is there and how it interacts with the ECU...ie... it's a good thing.... b/cause if it see too high temps (lean condition)... it tells the ecu and that corrects to prevent engine damage.

Seems like removing the sensor from the uppie and just having an EGT sensor at the maniforld wired to a in dash gauge, would not activly prevent damage in the case of a lean condition. It would just move the needle on the gauge and the ecu would know no different.

just my 0.02... thanks for the advice :)
 

·
Moderating on the run!
Joined
·
7,322 Posts
The oe probe really doesn't "interact" w/ the ECU, if it senses catsrophic high temps- ie the cat is burning up - it will put your car in limp mode.

If those temps were seen catless (ie they would be coming from the actual exhaust-not a cat burning up) your motor would already be fried.

Thus a EGT probe in the maniflod lets you know when things are getting heated up, many have warning peaks (red light/buzzer, etc) that can be programed in to let you know to get off the gas.

If the oe egt probe truely interacted w/ the ECU- ie temps too high lets pull some timing or add fuel- then your correct it would be worth keeping. But again it's only function in life was to tell the ECU that the cat is burning up- no cat- no need for the ecu.

Big Sky
 

·
Registered
Joined
·
42 Posts
great, thanks for the info.

Suppose, stock uppie with cat, stock egt sensor. If the sensor sees high temps and puts you in limp mode... has your engine already fried ?
 

·
Registered
Joined
·
1,547 Posts
Lud,
I would think imho that the O.E.M E.G.T would signal limp mod before catostrophic engine failure with a factory programed E.C.U
(if you were using the O.E.M catted Uppipe)

BUT, If we add in an aftermarket tuners programing say a "Stage 1-2" Then it seems to me if the tune was mixing on the lean side in some areas the sensor would catch the high E.G.T's to late to prevent some damage depending on what parameter the tune/engine crossed the line.

This is the reason that if I worried about a particuler tuner's tune going a little beyond the "safe" side in some driving situations I would install an aftermarket E.G.T in the exhaust cyl. manifold and moniter it instead of trusting the O.E.M E.G.T

There have also been reports that the O.E.M E.G.T when used in an aftermarket (Decatted) Upipe has failed, I would think the same situation could apply to the STI Upipe

BigSky is much more knowledgable in this area as a tuner so I would go with his ideaology

.02
Shotgun
 

·
Moderating on the run!
Joined
·
7,322 Posts
Ludecrous said:
great, thanks for the info.

Suppose, stock uppie with cat, stock egt sensor. If the sensor sees high temps and puts you in limp mode... has your engine already fried ?
I'm pretty sure- yes. The oe egt is only to prevent damage from the cat burning up. I can't remember the temp that the uppipe egt goes "off", but it was very, very high. If these temps were caused from actual egts from the engine (vs the cat frying) your motor would in all likely hood be fried.

Big Sky
 
1 - 17 of 17 Posts
Top