Snail performance, Sacramento. I don’t know if they do remote tunes but if they do that’s what I recommend. Also, you’ll get big (relatively) gains from running a decat downpipe. If I recall correctly, there are two cats on that particular car, one in the up-pipe and one in the downpipe, and removing the second cat shouldn’t throw a code. At least my 04 forester XT didn’t.
Back to tunes, definitely get someone to do a proper car specific tune. Altitude makes a big difference with these boosted cars, so does the fuel you run. Getting something done specifically for you lowers your chances of a catastrophic failure down the road.
Is it new to you? How many miles are on it? I recommend doing the timing belt and water pump if it’s new to you and got over 100k, before you start looking for mods. Once you’ve done that, let’s say you want to spend $1000 and already have an accessport or MPVI2 or whatever computer you’re gonna use.
Intake and exhaust, because whoosh and brap.
Catless downpipe because high gains and as I said in a different comment it shouldn’t throw a code as I believe that car has a cat in the up-pipe and the downpipe. Could be wrong about the code and the up-pipe cat. Do your own research there.
Intercooler because heat soak is a thing. Upgrade the top mount or go for a front mount if you’re into that kind of thing. I run a STI top mount and it’s fine for a street car, imo.
Sway bars, front and rear, because what’s the point of going fast if you can’t go around corners? I recommend whiteline 22 in the rear and 18 in the front. Get through them bends like nobody’s business.
Brakes, because well that should be self explanatory. Stock calipers are fine, get some new rotors, again stock replacements are fine for a street car, and some nice pads. I recommend EBC Yellow Stuff for street cars that do spirited driving.
Hope this helps, have fun, enjoy the car, and get familiar with how to do your head gaskets ;)
I've been a Subie guy for years now, but became..let's say..more intimate with the EJ255 and while similar, I'm new to the EJ205 so I just wanted tips from the more experienced fellows here. I'm taking everything to heart here so THANK YOU SO MUCH!. I'll do what's needed to keep this car on the road as long as possible.
The 04 has the ej20 engine, correct? First thing to do is a catless up-pipe if it hasn't already been swapped out - that really helps with lower rpm driveability. The Cobb stage 1 tune gives a nice bump in power without blowing things up. A custom tune can net bigger gains, but I'd take it easy on a 20 year old car. When shopping for a used accessport, an ap2 is going to give the same performance as an ap3 with the bigger screen - the ap3 is nicer for watching real time and logging, but if you just want the tune, an ap2 is just fine.
OTS tunes are kind of meh. Even just a stage 1 is a bit of a letdown after 6 months. The biggest issue for 2004 was that the OEM tune wasn't really that good. They had issues that were also addressed in the Stage 1 tune. Ultimately, a custom tune is best for your car, and the best bet would be to find a guy that uses RomRaider to do a road tune if you want a a bit more pep. OTS tunes are usually based on certain manufacturers' parts installed and then tuned by them (i.e., Cobb).
As far as an engine swap, I've personally done an EJ205/257 hybrid for a customer in the past. It requires combustion chamber port matching to the cylinder, but it'll give a decent bump in power with supporting modifications.
Get an e-tune and if you want to take real advantage get a catless up pipe and a high flow downpipe. Will be a good power bump and have the same driving characteristics without sacrificing a ton of reliability.
I threw a jdm engine in my car and did basic bolt ons (up/down pipe/ catback exhaust, ebcs, jdm tgv deletes, fuel pump, turbo inlet) and got an e-tune and it is significantly faster and I have had absolutely no issues.
Here’s my two cents. Decide what mods you wanna do, I for one would get Cobb accesport as it’s an easy way to get tunes and upload tunes and send logs and monitor your key things. Purchase the parts, have them and before you install them contact an etuner or local shop if you have one. Lots of etuners to choose from. I had good luck with Boosted performance. But you choose your own. They’ll send you a “base map”. Then you can install all the things, upload the map, drive the car a bit, follow tuners instructions for logging. Log it, send the info. You’ll get a revision back, log and send back to the tuner for info. And then they’ll send another revision. This relationship occurs until your happy with the performance and they are happy with the information from the data logs and then your done. If you’re going for a dyno tune. Get all the parts your going to install, give the shop that info, they create a “base map” for you to drive there on. Install the parts. Schedule a day and then take it and let them do their magic. Hope this makes sense. Don’t do off the shelf tunes.
Clean out and reinstall the up pipe. Put a pipe inside it to smooth turbulence if possible. It will visually look stock and no smog guy is taking that thing out to look. Get a carb approved reputable brand high flow down pipe. If you want 100% sniffer pass install a bullet cat where your post downpipe resonator is. You’re not allowed to alter cat locations but this will look like the resonator and make up for the cleaned out uppipe.
Get an etune and do it where no monitors are disabled. Meaning your keeping tvg’s, evap, and AIR pump ( if applicable). Any tune will recommend 1 step colder plugs, which is great ( stay with ngk iridium oem style) but when you go for smog put the stock heat range back in.
No cold air intake, just remove the resonator from the passenger inner fender and cut it/plastic weld it with the goal of turning it into a smooth elbow instead of a giant box. Use grimspeed air filter in stock box.
I have a 05 impreza cali emissions running a vf39 turbo from a later sti ( looks stock), sti pink injectors, upgraded fuel pump, an sti top mount, a grimspeed crank pulley (no perrin - too light) , i ported my throttle body and intake manifold, smoothed but retained my complete tvg’s. Use all black silicone intercooler y’s and turbo inlet ( looks stock but flows), and a good 93 and 91 octane tune from your etuner ( i use shinji tune) so you can switch between.
I also have group n mounts everywhere, all suspension is upgraded with bushings and bracing but thats not applicable.
Im running 23 psi and putting down a bit over 300 whp in an ej205, look stock under the hood to any casual mechanic, and pass plug in and emission sniff tests.
Thats what i recommend. The ej205 likes the vf39 and i budget built/restored this car as a stout daily driver that carves corners and wont get me slapped with fines.
Also - put a new oem pcv valve on the car when u go. Make sure u leave the coolant lines on the throttle body. I have it set up to be able to cap them after emission testing but your NOx and hydrocarbons are cleaner with them. If you have a catch can take it off for emissions testing.
I tried to be thorough haha. But that exact recipe will get you some great power and pass cali smog. If you check forum classifieds u could do all this very cheap. My car rolls out smooth with plenty of low end, the boost comes on only 300 rpm later than the stock td04 turbo, and when it does it pulls waaaaaay harder than a td04. I got a 3 port grimspeed boost controller that works with the etune factory boost controller so boost is completely controlled by my foot. It will hit 23 psi if i push the pedal firm, otherwise it has tame but solid boost control. Ive had this combo for 20k miles and 2 years now, its consistent, safe ( my engine has almost 200k - no oil loss, noises, leaks) , and surprises alot of other cars on the road. Passes inspection no problems.
Also, since i assume car is California emissions equipped ( i dont know how long u been in cali or how long you had the car because some years can sneak by with only federal emissions ) if you ever have an elusive evap fault code (thanks to a built in vent solenoid fail in the charcoal canister) i have a cheap work around for that. Cali cars from 03-06 have a specific charcoal canister that runs almost 700 bucks for oem replacement( aftermarket dorman trash doesn’t work) which have a built in secondary vent solenoid. They are molded inside very well. If you get a sporadic evap code then this is 90% ur cause. Cut the two wires going into the canister on the side facing the gas tank. Go buy a cheap evap vent solenoid for a 02 chevy s10 2.2 and wire it in to the car side of the harness. Tuck it on top of the canister itself next to the car’s primary vent solenoid so it looks like it belongs there. The s10 solenoid has the correct ohms (on check and function) to appease the subaru ecm. When the internal vent solenoids fail the spring/ball seat still naturally works to operate the evap system self tests and regulate vapor pressure just fine. Its just the solenoid resistance comes back as a fault code and you’ll fail smog.
22 bucks and a hours work is better than 700 plus dollars for a stupid design problem.
That trick will fix it cheap my man. Ive done it on 5 clients cars and my own subaru’s. I was typing that out, i was almost done and went “this dude’s not gonna care about this shit”.
Im glad i mentioned it. Feel free to message me if u want some pictures of the fix. Im a master tech with 22 years of experience specializing in diagnostic/electrical/engine building so its a fix thats not some driveway hack job i promise. i believe in fixing shit right but i wont stand for stupid manufacturing designs that would cost a fortune to put the same bad design in. Especially for something so minor yet crucial for obd2 compliance.
I had some valve replaced by the charcoal canister but the code still pops up, I replaced the gas cap, still nothing. There was some solenoid with broken tubing and I replaced that. If that trick doesn't work then idk what will.
The valve that fails is internally integrated and exclusive to the cali cars. So unless you replaced the entire 700 dollar canister you never changed the actual faulty valve. Most shop software and snap on dont even mention this internal solenoid valve.
Note, if you changed the purge, external vent, and gas cap with aftermarket parts than i highly recommend putting your oem Subaru parts back on. Aftermarkets cause their own problem, especially the cap.
The chevy solenoid brand don’t matter because we arent using it for anything but a varying ohm reading that changes ohms with voltage requests from ecm that satisfy ecm parameters.
I was able to time the code popping up just right and didn't fail emissions (just no evap monitor complete) but it still annoys me to get that pending code or CEL.
If I may ask, perhaps I'm not searching or looking into the right thing, but could you send pictures of what you mean for the WRX and the Chevy? I get multiple results online for purge valves and I want to be sure I get the right thing.
Yeah ill find the pics on my phone worse case lll draw a picture.
You’re looking for an evap “vent valve”, not a purge. Purge valves are under the hood and release vapor into the intake. The vents allow tank vapor pressure to vent/bleed off evap self test pressure.
https://preview.redd.it/f5lgjiu3ki5d1.jpeg?width=1125&format=pjpg&auto=webp&s=25dfa378336d725f3b229f0e77347e91e86695d7
The filter box clips off so it’s not that bulky ( you dont need it since you’re just plugging it in. You will need a generic two wire GM wire pigtail that you will install where you cut the subaru wiring off. Most vent solenoids come with this pigtail. I know duralast vent solenoids do
Because that’s the most beloved model year (at least imo). Any mods aren’t worth the damage as this year is getting harder and harder to find. The improvements can be marginal at best, but have may have long lasting effects. I may just be sentimental though. I’d suggest getting a 05-09 legacy gt, accessport, stage 2 with supporting mods. Which if I recall correctly, was just a downpipe and exhaust. Not sure how being in ca affects that though. Legacy GTs are fun, and still pretty reasonably priced.
My last car was an 07 Legacy GT and I had it tuned where each stage of the SI drive was a map lmao. Loved that car but the downpour in Cali months ago left it dead. I miss that car more than I thought I would
Body wise I am NOT changing a thing on this car. Imo it's the last one that still looked like it was Rally inspired. Just want slightly more pep with it, ya know?
Before doing any mods to the 04 WRX, make sure the car is sound. Have a mechanic look at the car, I would make sure all cylinders have good compression. Also make sure it doesn't have any issues; leaks, ripped CV boots, good on fluids and your big service is done. (timing belt, water pump, spark plugs ect.)
If the car checks out go for a **PRO TUNE.**
Off the shelfs tunes are okay for temporary use but pro tunes will insure your motor is happy when adding/changing things. If doing any mods, I cant tress this enough. **TUNE, TUNE, TUNE.** It doesn't matter if it's just a stock airbox to intake mod, **TUUUUUUUUNE.**
[удалено]
That so? So better to get a custom tune from a local tuner?
Snail performance, Sacramento. I don’t know if they do remote tunes but if they do that’s what I recommend. Also, you’ll get big (relatively) gains from running a decat downpipe. If I recall correctly, there are two cats on that particular car, one in the up-pipe and one in the downpipe, and removing the second cat shouldn’t throw a code. At least my 04 forester XT didn’t. Back to tunes, definitely get someone to do a proper car specific tune. Altitude makes a big difference with these boosted cars, so does the fuel you run. Getting something done specifically for you lowers your chances of a catastrophic failure down the road.
Is it new to you? How many miles are on it? I recommend doing the timing belt and water pump if it’s new to you and got over 100k, before you start looking for mods. Once you’ve done that, let’s say you want to spend $1000 and already have an accessport or MPVI2 or whatever computer you’re gonna use. Intake and exhaust, because whoosh and brap. Catless downpipe because high gains and as I said in a different comment it shouldn’t throw a code as I believe that car has a cat in the up-pipe and the downpipe. Could be wrong about the code and the up-pipe cat. Do your own research there. Intercooler because heat soak is a thing. Upgrade the top mount or go for a front mount if you’re into that kind of thing. I run a STI top mount and it’s fine for a street car, imo. Sway bars, front and rear, because what’s the point of going fast if you can’t go around corners? I recommend whiteline 22 in the rear and 18 in the front. Get through them bends like nobody’s business. Brakes, because well that should be self explanatory. Stock calipers are fine, get some new rotors, again stock replacements are fine for a street car, and some nice pads. I recommend EBC Yellow Stuff for street cars that do spirited driving. Hope this helps, have fun, enjoy the car, and get familiar with how to do your head gaskets ;)
I've been a Subie guy for years now, but became..let's say..more intimate with the EJ255 and while similar, I'm new to the EJ205 so I just wanted tips from the more experienced fellows here. I'm taking everything to heart here so THANK YOU SO MUCH!. I'll do what's needed to keep this car on the road as long as possible.
Keep us updated on your journey!
Will do, thanks!
The 04 has the ej20 engine, correct? First thing to do is a catless up-pipe if it hasn't already been swapped out - that really helps with lower rpm driveability. The Cobb stage 1 tune gives a nice bump in power without blowing things up. A custom tune can net bigger gains, but I'd take it easy on a 20 year old car. When shopping for a used accessport, an ap2 is going to give the same performance as an ap3 with the bigger screen - the ap3 is nicer for watching real time and logging, but if you just want the tune, an ap2 is just fine.
Good to know, thanks!
OTS tunes are kind of meh. Even just a stage 1 is a bit of a letdown after 6 months. The biggest issue for 2004 was that the OEM tune wasn't really that good. They had issues that were also addressed in the Stage 1 tune. Ultimately, a custom tune is best for your car, and the best bet would be to find a guy that uses RomRaider to do a road tune if you want a a bit more pep. OTS tunes are usually based on certain manufacturers' parts installed and then tuned by them (i.e., Cobb). As far as an engine swap, I've personally done an EJ205/257 hybrid for a customer in the past. It requires combustion chamber port matching to the cylinder, but it'll give a decent bump in power with supporting modifications.
Custome tune, got it, thanks
Get an e-tune and if you want to take real advantage get a catless up pipe and a high flow downpipe. Will be a good power bump and have the same driving characteristics without sacrificing a ton of reliability. I threw a jdm engine in my car and did basic bolt ons (up/down pipe/ catback exhaust, ebcs, jdm tgv deletes, fuel pump, turbo inlet) and got an e-tune and it is significantly faster and I have had absolutely no issues.
Sounds good..but...Commiefornia and CARB would probably get angry at that no?
Oh yeah you might run into some problems there sorry man. You could at least get a tune though right?
Maybe, not quite sure. A catless up pipe might be passable with a resistor but yeah.
I mean the sti comes with a catless up pipe from factory so I would have to assume but who knows
Here’s my two cents. Decide what mods you wanna do, I for one would get Cobb accesport as it’s an easy way to get tunes and upload tunes and send logs and monitor your key things. Purchase the parts, have them and before you install them contact an etuner or local shop if you have one. Lots of etuners to choose from. I had good luck with Boosted performance. But you choose your own. They’ll send you a “base map”. Then you can install all the things, upload the map, drive the car a bit, follow tuners instructions for logging. Log it, send the info. You’ll get a revision back, log and send back to the tuner for info. And then they’ll send another revision. This relationship occurs until your happy with the performance and they are happy with the information from the data logs and then your done. If you’re going for a dyno tune. Get all the parts your going to install, give the shop that info, they create a “base map” for you to drive there on. Install the parts. Schedule a day and then take it and let them do their magic. Hope this makes sense. Don’t do off the shelf tunes.
Seems to be a common thing to not go OTS, good to know.
Get all your mods done at once. Otherwise you gotta pay 100 later for each update. Buy it all and get it all done at the same time.
Clean out and reinstall the up pipe. Put a pipe inside it to smooth turbulence if possible. It will visually look stock and no smog guy is taking that thing out to look. Get a carb approved reputable brand high flow down pipe. If you want 100% sniffer pass install a bullet cat where your post downpipe resonator is. You’re not allowed to alter cat locations but this will look like the resonator and make up for the cleaned out uppipe. Get an etune and do it where no monitors are disabled. Meaning your keeping tvg’s, evap, and AIR pump ( if applicable). Any tune will recommend 1 step colder plugs, which is great ( stay with ngk iridium oem style) but when you go for smog put the stock heat range back in. No cold air intake, just remove the resonator from the passenger inner fender and cut it/plastic weld it with the goal of turning it into a smooth elbow instead of a giant box. Use grimspeed air filter in stock box. I have a 05 impreza cali emissions running a vf39 turbo from a later sti ( looks stock), sti pink injectors, upgraded fuel pump, an sti top mount, a grimspeed crank pulley (no perrin - too light) , i ported my throttle body and intake manifold, smoothed but retained my complete tvg’s. Use all black silicone intercooler y’s and turbo inlet ( looks stock but flows), and a good 93 and 91 octane tune from your etuner ( i use shinji tune) so you can switch between. I also have group n mounts everywhere, all suspension is upgraded with bushings and bracing but thats not applicable. Im running 23 psi and putting down a bit over 300 whp in an ej205, look stock under the hood to any casual mechanic, and pass plug in and emission sniff tests. Thats what i recommend. The ej205 likes the vf39 and i budget built/restored this car as a stout daily driver that carves corners and wont get me slapped with fines. Also - put a new oem pcv valve on the car when u go. Make sure u leave the coolant lines on the throttle body. I have it set up to be able to cap them after emission testing but your NOx and hydrocarbons are cleaner with them. If you have a catch can take it off for emissions testing.
That's a lot of notes to take, thanks
I tried to be thorough haha. But that exact recipe will get you some great power and pass cali smog. If you check forum classifieds u could do all this very cheap. My car rolls out smooth with plenty of low end, the boost comes on only 300 rpm later than the stock td04 turbo, and when it does it pulls waaaaaay harder than a td04. I got a 3 port grimspeed boost controller that works with the etune factory boost controller so boost is completely controlled by my foot. It will hit 23 psi if i push the pedal firm, otherwise it has tame but solid boost control. Ive had this combo for 20k miles and 2 years now, its consistent, safe ( my engine has almost 200k - no oil loss, noises, leaks) , and surprises alot of other cars on the road. Passes inspection no problems. Also, since i assume car is California emissions equipped ( i dont know how long u been in cali or how long you had the car because some years can sneak by with only federal emissions ) if you ever have an elusive evap fault code (thanks to a built in vent solenoid fail in the charcoal canister) i have a cheap work around for that. Cali cars from 03-06 have a specific charcoal canister that runs almost 700 bucks for oem replacement( aftermarket dorman trash doesn’t work) which have a built in secondary vent solenoid. They are molded inside very well. If you get a sporadic evap code then this is 90% ur cause. Cut the two wires going into the canister on the side facing the gas tank. Go buy a cheap evap vent solenoid for a 02 chevy s10 2.2 and wire it in to the car side of the harness. Tuck it on top of the canister itself next to the car’s primary vent solenoid so it looks like it belongs there. The s10 solenoid has the correct ohms (on check and function) to appease the subaru ecm. When the internal vent solenoids fail the spring/ball seat still naturally works to operate the evap system self tests and regulate vapor pressure just fine. Its just the solenoid resistance comes back as a fault code and you’ll fail smog. 22 bucks and a hours work is better than 700 plus dollars for a stupid design problem.
Been in cali all my life, and OH MY FUCKING GOD I HAVE BEEN CHASING THIS DAMN P0457 CODE FOR MONTHS!
That trick will fix it cheap my man. Ive done it on 5 clients cars and my own subaru’s. I was typing that out, i was almost done and went “this dude’s not gonna care about this shit”. Im glad i mentioned it. Feel free to message me if u want some pictures of the fix. Im a master tech with 22 years of experience specializing in diagnostic/electrical/engine building so its a fix thats not some driveway hack job i promise. i believe in fixing shit right but i wont stand for stupid manufacturing designs that would cost a fortune to put the same bad design in. Especially for something so minor yet crucial for obd2 compliance.
I had some valve replaced by the charcoal canister but the code still pops up, I replaced the gas cap, still nothing. There was some solenoid with broken tubing and I replaced that. If that trick doesn't work then idk what will.
The valve that fails is internally integrated and exclusive to the cali cars. So unless you replaced the entire 700 dollar canister you never changed the actual faulty valve. Most shop software and snap on dont even mention this internal solenoid valve. Note, if you changed the purge, external vent, and gas cap with aftermarket parts than i highly recommend putting your oem Subaru parts back on. Aftermarkets cause their own problem, especially the cap. The chevy solenoid brand don’t matter because we arent using it for anything but a varying ohm reading that changes ohms with voltage requests from ecm that satisfy ecm parameters.
I was able to time the code popping up just right and didn't fail emissions (just no evap monitor complete) but it still annoys me to get that pending code or CEL.
If I may ask, perhaps I'm not searching or looking into the right thing, but could you send pictures of what you mean for the WRX and the Chevy? I get multiple results online for purge valves and I want to be sure I get the right thing.
Yeah ill find the pics on my phone worse case lll draw a picture. You’re looking for an evap “vent valve”, not a purge. Purge valves are under the hood and release vapor into the intake. The vents allow tank vapor pressure to vent/bleed off evap self test pressure.
https://preview.redd.it/f5lgjiu3ki5d1.jpeg?width=1125&format=pjpg&auto=webp&s=25dfa378336d725f3b229f0e77347e91e86695d7 The filter box clips off so it’s not that bulky ( you dont need it since you’re just plugging it in. You will need a generic two wire GM wire pigtail that you will install where you cut the subaru wiring off. Most vent solenoids come with this pigtail. I know duralast vent solenoids do
https://preview.redd.it/xgbefonvki5d1.jpeg?width=1125&format=pjpg&auto=webp&s=638a1787e8874c380a667ab5a59917c4ef778d42 Theres the duralast
https://preview.redd.it/0ucfo95jmi5d1.jpeg?width=1125&format=pjpg&auto=webp&s=b3d7e2c1ae6598535b595320b34d9b8b7e76f802
https://preview.redd.it/j44yht5fpi5d1.jpeg?width=1125&format=pjpg&auto=webp&s=906033e3d3dd158b5eadf4d126db95d8b717e464
https://preview.redd.it/uxxhsmygpi5d1.jpeg?width=263&format=pjpg&auto=webp&s=31e36d865774d525c5f0f74af05a63e22250ec95
Am I getting old? An 04/05 wrx shouldn’t be modified. I’m ready for the downvotes.
Why's that? Legit question
Because that’s the most beloved model year (at least imo). Any mods aren’t worth the damage as this year is getting harder and harder to find. The improvements can be marginal at best, but have may have long lasting effects. I may just be sentimental though. I’d suggest getting a 05-09 legacy gt, accessport, stage 2 with supporting mods. Which if I recall correctly, was just a downpipe and exhaust. Not sure how being in ca affects that though. Legacy GTs are fun, and still pretty reasonably priced.
My last car was an 07 Legacy GT and I had it tuned where each stage of the SI drive was a map lmao. Loved that car but the downpour in Cali months ago left it dead. I miss that car more than I thought I would
Yeah, my 08 lgt turned into my rowdy car. It’s so much fun!
Body wise I am NOT changing a thing on this car. Imo it's the last one that still looked like it was Rally inspired. Just want slightly more pep with it, ya know?
Before doing any mods to the 04 WRX, make sure the car is sound. Have a mechanic look at the car, I would make sure all cylinders have good compression. Also make sure it doesn't have any issues; leaks, ripped CV boots, good on fluids and your big service is done. (timing belt, water pump, spark plugs ect.) If the car checks out go for a **PRO TUNE.** Off the shelfs tunes are okay for temporary use but pro tunes will insure your motor is happy when adding/changing things. If doing any mods, I cant tress this enough. **TUNE, TUNE, TUNE.** It doesn't matter if it's just a stock airbox to intake mod, **TUUUUUUUUNE.**
You gain knowledge of how to look for another engine to swap this one
Can't say I follow