As of a few hours ago i own my first turbo car, and my first subaru in many years: a 2006 baja turbo automatic.
Its got some needs, and i have some wants. Having never been a subaru guy (i owned 3 or 4 over the years as appliances) im new at this whole thing. Ive never had any forced induction before.
Engine:
Known Needs: timing belt, valve cover gaskets, all fluids, tune up, filters, rear trans seal leaking significantly onto cats, exhaust garbage. Is there other need to do maintenance that i dont know about? Its sitting at 204xxx and is a complete unknown as far as history.
Known wants: faster!!! Im thinking better flowing intake and exhaust parts since im already in there. Apparently some stuff from the forester xt fits? I gather from reading i want a catless uppipe and bigger downpipe? And an intake? Im looking just for challenge budget power here. Id also like to improve throttle response while im at it. Seems kind of soggy.
Chassis:
Known needs: fluids and filters. Ac needs charged. Theres reported rust in brake lines at the back junction, but i cant seem to locate it. Struts are definitely not healthy. Brakes are funky feeling. Clicking from dead stop that feels like either cv shaft or driveshaft hitting. Looks like rear trans moint collapsed. Address some surface rust. Seat heaters inop, seats only semi-move. What needs am i not thinking of? What don't i know yet?
Wants: better sway bars, lowered. Killer ac. Killer brakes.
General: what interchanges with what? Amy turbo special maintenance? Any reason NOT to free up intake and exhaust?
This is to be a daily driver, and 2025 challenge car. So keep all that in mind.
What other information do we need, or what am i not asking or thinking of?
Thanks yall!!
It's junk you should definitely pass it along to someone with subaru experience (me)
In reply to Patrick :
Nope. But ill give you first dibs when I get tired of it!
Don't put on an intake without a tune. Do remove the snorkus for sweet turbo noises. Or I have a complete rotated holset he341 setup if you wanted to go for challenge glory lol.
Also, just what all can I do without having to tune it? All that is available is romraider, and i am no tuner....
Dusterbd13-michael said:
Snorkus?
The big muffler in the right front fender. It does not hurt power but it prevents you from hearing turbo whistle.
Dusterbd13-michael said:
Also, just what all can I do without having to tune it? All that is available is romraider, and i am no tuner....yet.
Fixed that for you.
Download and get romraider working even if you aren't going all the way with a tactrix openport and tuning. A simple VAG OBDII cable from amazon will work for reading romraider logger which is very useful. You can datalog, watch the live stream of data and reset codes. It will give you a lot more information than a generic OBDII reader will so worth the bit of trouble to setup.
As a daily these things like lots of premium so keep that in mind.
In reply to Dusterbd13-michael :
My understanding is that these cars require tunes for even minor changes. It's not uncommon for them to lose power with mods without a tune. Besides, the intake and exhaust are not that bad performance wise, more boost from the tune is where most of the cheap power is.
On the soggy feeling, check that the wastegate flapper is covering the wastegate hole. They are known to walk and uncover part of the hole, leading to lots of lag, especially for a smallish turbo on a biggish engine.
I think the standard recipe for this engine is tune with the up and down pipes, which should be good for close to 300hp/300tq. That is for the Legacy GT version, which I believe is largely similar.
Preventative fixes...
The banjo bolt filter for the turbo is known to plug and kill the turbo. Change, clean, or just remove it. Oil change history is a big factor. Mine was clean at 140k plus on a car that saw consistent oil changes. The oil pump pickup is known to crack. Later Subaru or aftermarket pickups are a good idea if you are in there. If you are at 200k on the original motor, I'm guessing you didn't get a problem one.
FWIW, it should be very easy to brake torque the EJ255 up to 8psi, at which point you will start to overpower the brakes.
Biiiig difference from the EJ205 in the early vehicles.
With that sort of mileage leaning on it at all could get very expensive. You need to know your oil consumption and compression/leakdown numbers. Get an app and an OBD dongle so you can monitor/record boost and AFR numbers so you know what is happening. These tend to run lean and create all sorts of issues.
At this point I would bet you have at least one piston with broken ring lands. If the AVCS screens are still in there you may not be getting any decent action from that system. All your rubber lines are cracked and leaking so it is even leaner than it should be. Your valves are out of adjustment, they are mechanical so they need shims to fix that.
My motor had 90 to 110 psi, burned a quart of oil every 2 tanks of gas and leakdown was around the 80s. Then it got worse. A complete rebuild later it runs great stock. 12psi no oil burning and 25 mpg at 75. I have no intention of beating on it, spent more on the motor than I did buying the car. And it is so frickin heavy it makes no sense to go after most other cars.
Sorry but you need a dose of reality. A turbo suby with over 180K miles is not a candidate for more boost. Unless you are entered in an engine blow contest.
In reply to porschenut :
If he has had a piston swap for lower compression, I would assume they are forged. Or at least have the ring gaps a bit loosened up.
For sure the head gaskets were replaced when the pistons were changed so let's bequiet the peanut gallery right now before it starts 
On that tip, there are plugs in the engine block for wristpin access. One plug and one cover for the rear two, if memory serves correctly, and plugs in both fronts. Those can leak too.
The EJ255 failures I seen were burnt exhaust valves and, somehow, one with fragged thrust bearings. And interestingly enough they were all Bajas.
I am 99% sure that 2.5 turbos did not have cats in the uppipe before 2008. The EJ255/257 uppipe is a performance upgrade for the EJ205 unit, which did have a converter.
I don't think turbo Subaru folks are the right place to seek wisdom! 
I've got an 05 Outback XT that's powertrain similar to your Baja.
With that kind of mileage, just make sure you're keeping the little bit of oil still inside of it, and try and hunt down all the leaks.
Check the oil level often, and these EJ255's had a 3750 mile oil change interval. (See TSB Service Bulletin # 02-103-07)
The heat from the turbo and the age of the rubber, means you'll have a mess of vacuum, coolant, and oil lines that are likely brittle. I just did the "few" ones hidden under my intake manifold:
As far as performance, up pipe (05's did have cats), downpipe, and tune are the biggest bang for the buck. For laggy performance, do a boost leak check. The intercoolers leak, the turbo inlets tear, and there's various other spots the boost'll get out. Brakes are garbage, but interchange with lots of other Subarus if you need to source pads or larger brakes.
I think the turbo oil screen thing is overblown, mine have been clean every time.
Enjoy it as a daily! Turbo Subarus are very easy to ruin as a DD as you add power, grip, and because racecar.
What are the avcs screens?
And im soaking all this stuff in. Please keep it coming! Hadn't thought about all the rubber underhood being cooked by turbo heat. Will DEFINITELY have to check everything with a fine tooth comb and smoke machine.
AVCS is a cam advance, or retard I forget actuated electronically and driven by oil pressure. They put little screens in the passage that tended to trap crap and stop flow. The whole AVCS system relies on clean oil.
I have only had 2 motors that destructed, one was lack of coolant and the other was cracked lands. A few suby tech buddies said most turbo motors probably have cracked lands for a while before big problems arise. Mine had a few old cracks but the top land broke and gouged the cylinder. It's your money but leaning on boost or changing the tune for power may end up with a complete rebuild. Doing some research into condition first is a good path and will teach you much about these motors.
If he has had a piston swap for lower compression, I would assume they are forged. Or at least have the ring gaps a bit loosened up.
- I have no idea where a piston swap came into the discussion. It sounded to me like the motor was stock.
And my up pipe has a cat, luckily. That trapped the broken piston bit and saved the turbo from destruction.
So, the piston swap comes from dollraves, who i got the carfrom. The person she got it from (3rd owner) stated second owner swapped pistons to prep for bigger turbo. No documentation available on that, so no ideas on what/when.
In reply to Dusterbd13-michael :
Any way to bore scope and see the pistons? Not that I can ID them but someone may be able to.
In reply to Stampie :
Not a horrible idea. I don't have a bore scope, but this may be a good excuse! Sinch ill have valve covers off anyway at some point....
The single AVCS system advances the intake only cams at lower RPMs to improve boost response. Their 0 oil pressure state is the high RPM desired position.
The Dual AVCS does the same on the intake but works opposite on the exhaust. My understanding is In a Dual AVCS motor the exhaust Cams are in their Low RPM position with 0 oil pressure and retard the cams as oil pressure increases.
That is apparently what makes Dual AVCS JDM swaps more challenging because you can't just not use the AVCS system.
In reply to nocones :
The JDM swaps are challenging in part because they are different from US market cars. The cam sensor tooth patterns are different. Why? Because why not.
And, I gather, the solenoids and such are also different from US market cars, so if you have a bad one you can't just pop over to the Subaru dealer and buy a new one.
It has been a couple years since I was researching all this.... wanted to buy a Japanese market engine for "Colin", but all of the can't-get-there-from-here turned me off of that. The variable cam timing would have been interesting to play with, apparently it is worth over 1000rpm of boost onset (!!) compared to fixed timing.
Dusterbd13-michael said:
Also, just what all can I do without having to tune it? All that is available is romraider, and i am no tuner....
Nothing.
I learned how to tune on my Legacy GT. I miss that car
