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cBax's OBXT build

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2005 Outback XT, Atlantic Blue Pearl/Granite Gray Opal

109k miles at time of purchase, bone stock w/ 5EAT



Purchased the XT this past Saturday (7/18/15) in a private sale for $5700. Interior is rough, several scratches in the paint and huge dent in the hatch. Seemed to drive ok (worn out suspension) and pulled smoothly through the revs. I found out I know one of the guys that has been working on it and knows the history (old couple, dealer serviced (carfax confirms)), just drove it a few weeks ago and says its as good as it gets mechanically. No rust, so I made the guy an offer, paid cash and drove it ~50 miles home. Other than a slight stumble at idle and not knowing exactly how the turbo and tq convertor should feel, everything seems normal. Just planned to do a tune up, replace the majority of the suspension components and slowly upgrade it.


Biting into the crapsandwich

Cleaned the engine bay up, removed a grocery bag of pine needles and dirt from under the cowl the night I got it home. Monday night I was putting tags on it and figured Id clean the maf and take it for a spin around the block. Noticed a rattle that would come and go with part throttle between 3-4k. Any more or less throttle would make it go away. Did some googling and scared myself into the worst scenario (rod knock). Called up the friend that had been involved with the car and asked if I could bring it to him to get a set of seasoned boxer ears to confirm or deny my suspicion. So I drove it to work on Tuesday. No noises, everything seems fine. I get off the highway and Im manually shifting to listen for the noise...Its louder than ever. Oh no. Get 20 yards from my office and decide to go another block to listen further, accelerate and I get the moan of a banshee from under the hood, followed by a clank clank clank and it dies. No restart. So I push it to the side of the road and walk across the street to get a co-worker with a truck and tow strap. Another co-worker uses his AAA to get it back to my house. Neighbor came by later that night to check it out. Got it fired and it sounds like a rod is about to exit the block. :mad: Oil is still full. I think I can see slight small shiny bronze particles. Im going to drain and cut the filter open, but I think we all know its done. Im just not 100% positive whether is a rod or a piston.









For real?








I hate dirty motors




Getting over the crapsandwich hangover and making a plan

My pre-purchase goal was eventually to hit 320-350 whp/wtq and a Legacy suspension setup that isn't too harsh. Its going to be the family wagon, so some of it needs to be reasonable. The only part of that plan that is really changing is the timing of it. Im looking at shortblock options in case this one isn't salvageable. But may just do a new one anyways. Im going to have a hard time taking all these rusty exhaust parts off and putting them back on. As well as the turbo. So its going to get expensive really quick. I just need to sit down and prioritize it all and see what definitely needs to happen now vs later.


Im going to have a ton of questions, as Ive never built or tuned a Subaru before. But I fully intend to do it all. Ive downloaded the ROM and it all looks very familiar to what Im used to with other platforms. Ive got a lot of experience tuning Evos and Ive been dyno tuning my Mazda 3 on a fellow autocrosser's dyno at his house. He's upgrading it to AWD this fall, so the XT should see quite a bit of dyno time as I love doing it.


Stay tuned for updates.

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The plan.

Black = stuff I think I might do

Blue = purchased, awaiting install

Green = installed




- OEM EJ255 w/ forged Manley drop-ins

- Killer B Oil pickup and windage tray

- rebuilt heads w/ Inconel ex valves

- ARP Head studs

- JDM TGV Deletes

- Gates Timing set w/ Kevlar belt

- Grimmspeed Crank Pulley

- injectors

- fuel pump

- Group N motor mounts

- VF52

- Perrin Turbo Inlet

- Samco BPV hose

- Grimmspeed coated Uppipe & Crosspipe (DEI wrapped)

- Cobb catted downpipe (DEI wrapped)

- some sort of cat back (AVO?, Nameless?, Single Exit?)

- sick nasty cbax tune


- rebuild 5EAT

- valve body mod

- convertor



- LGT front calipers

- LGT Centric blank front rotors

- Hawk HPS 5.0 front pads

- Mevotech AL front LCAs

- Perrin front sway bar

- Moog front endlinks

- Coilovers

- Legacy subframe parts

- New bushings everywhere

- Rear sway bar



- wide ones



- Cubby gauge pod

- Vent gauge pod


- Autometer ES Boost, Oil Pressure, Trans Temp gauges

- New carpet

- New seats

- Paint/refinish/replace several interior pieces



- replace hatch and rear bumper

- Paint (potential color change)

- tint windows

- rustproof/undercoat as suspension and drivetrain bits get swapped.

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Im leaning towards a new EJ257 if I go new. But to be honest...haven't done a ton of research. It just appears to be the easy button. I do think Id want to upgrade to forged pistons even if I did the new EJ257.


2nd post updated with current/planned modifications. Very high level at this point. Ive got several things selected and put in my spreadsheet for reference, but need to do a ton more research before jumping on any parts right now.

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im running a rallispec short block with a blouch td05h-18gxt and ccouldnt be happier with it. put down north of 440wtq@21 psi on the dyno. but backed it off down to 380whp/364wtq@19psi to conserve the 5mt stock trans.
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That's on e85 I'm guessing since a 18g is a 430crank hp turbo. My TR 18g billet is rated lower at 400 crank. i put down 335/377wtq on 93oct 22.5psi on a stock ej255.

If you plan 350+ 4032 pistons are a must. I have a 6spd so my tuner didn't worry about the extra tq.

bikerx500 glad to hear it. If i can't build my spare block i plan on rallispec or ej207 v7.

cbax you have a lot of options. these cars have quite the parts list you can use.

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I know. Thats sort of what makes it so hard!


Im trying to get the seller and I's mutual friend/mechanic over to listen to the motor for a second. Seller says he'll "help me out" if our mutual friend is involved with the diagnosis. Hoping he's decent enough to give me back some cash, but I cant expect anything.


Got to thinking about the noises and what had transpired. There was a oil puddle under the car when I parked it after pushing it off to the side of the road, but no puddle after we towed it or at home. When I went to check the oil at home, the dip stick was sticking out 1/2" or so out of the tube and there was oil on the bottom of the engine cover. This thing had a slight stumble at idle. Thats why I cleaned the MAF.


Anyone else think a piston let go? And thats what caused excessive crank pressure to blow the dipstick out? And the rough idle? If I had to choose, Id rather it be a bearing, so at least the heads are less likely to be damaged.


Hoping to pull it within a week, yank the heads off and go from there.

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That's on e85 I'm guessing since a 18g is a 430crank hp turbo. My TR 18g billet is rated lower at 400 crank. i put down 335/377wtq on 93oct 22.5psi on a stock ej255.

If you plan 350+ 4032 pistons are a must. I have a 6spd so my tuner didn't worry about the extra tq.

bikerx500 glad to hear it. If i can't build my spare block i plan on rallispec or ej207 v7.

cbax you have a lot of options. these cars have quite the parts list you can use.


only running 93 oct. in mine since the closest e85 is 40 minutes so not worth the tuning or drive. also my blouch 18g is running with 3 inch inlet and a 10cm hot side. baseline run for the dynotune was stopped halfway when numbers reached 440wtq@4000rpm since im only running stock 5 speed. it was done on a mustang dyno and for now im only at 380hp/364tq to the wheels.


anyway i do have to agree with you that the parts available for these cars is getting closer and closer the wrx/sti catalog, lol and getting better all the time. here's to hoping it is something stupid and you will have some time to do what you want to the car as it seems to be relatively clean for the body(other than tailgate/bumper). goodluck with diagnosing the trouble man.

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Going to look at a LGT part out today. Was originally interested in the long block, but Ive decided to wait and see what condition mine is in. So for now Im just going to look at suspension/subframe parts.


Leaning towards the std rallispec block (if I need one) and a 6starspeed billet BB 18g. Seems to be a good deal, although I cant find any boost plots or results from that specific turbo.


What is the difference between wrx and sti turbo fitment? Is it the inlet of the TMIC? And the outlet is also different to match up with the throttle body?

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What is the difference between wrx and sti turbo fitment? Is it the inlet of the TMIC? And the outlet is also different to match up with the throttle body?


Looks like we have a specific TMIC and wrx/sti fitment turbos require some custom piping and specific TMIC that works.


Sooo. If Im in the market for a turbo and TMIC, what combo will be easiest to adapt and cheaper in the long run? Seems like it may make sense to abort LGT/OBXT fitment and just buy stuff that works together. Im considering FMIC, but for the moment leaning toward TMIC.

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If the bearings are shot in this motor, does that immediately mean the turbo needs to be rebuilt/replaced? Im trying to put a timeline and priority to the purchase of the parts and part of me wants to step through the mod process. But I don't want to kill a 4k shortblock just because I didn't do the turbo swap that I plan to do anyways.


Right now my priorities are:

- Short block, head rebuild, timing belt, water pump, TGV delete, reseal

- EBC solenoid

- AEM UEGO and boost gauge, logged through the TGV inputs

- crossover pipe, up pipe (rusty)

- downpipe (rusty)

- cat back (rusty)


possibly delay

- turbo (VF52 or BB 18G?)

- intercooler (FMIC or TMIC?)

- F1 valve body

- trans rebuild

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Yes more than likely. And all oil flow products would be replaced. IE oil cooler and pump. some replace the pan and pickup as well. I suggest Killer b pan and pickup since the oem pickup cracks and extra oil is great for these cars.

Get any new exhaust components ceramic coated. Like the up and down and if you get a header.

VF52 will be cheaper the BB 18g will be more powerful. with a built motor i suggest at least a BB20g and a fuel system. Then turn it down to what you want.

Go tmic like grimmspeed. FMIC is nice but what a headache to install.

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Bought a few goodies today. Gauges, gauge pods and exhaust. I may port my stock manifolds. Not really sure how far off the ports are yet and how much clean up is needed.


Im scaling back a tad on the shortblock and just going to run oem. Now the question is...oem VF52 or BB 18g?


Plan is to start pulling the motor this weekend.


Updated 3rd post with highlighted items purchased.

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Pulled the trigger on the Rallispec shortblock. :)


Also went ahead and got some head studs and a gasket kit. Still need a timing set, water pump, oil cooler, few more gaskets, few lines and hoses, and to pick a turbo. Depending on the turbo fitment (sti vs lgt), I may run the stock TMIC and injectors until its broken in just to help with the tuning aspect.

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Nice congrats. I have a dw65c for sale for cheap. Keep an eye on the boards side feeds go up for sale all the time. just get them cheap enough that you can send them out to be cleaned and flowed. used good parts are better than cheap chinese parts any day.
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  • 1 month later...

Its been a while since my last update. Not a whole lot (or any really) progress.


Since then, Ive:

- Moved the car from one side of the driveway to the other.

- Decided to walk away from the project, sell it as-is and take a loss

- Canceled the Rallispec block and Nameless cat-back orders

- Bought a new autocross car

- Left OBXT to sit in the driveway

- Went on a cruise through the mountains in my wife's 2.5i limited

- Decided her 2.5i was way too boring and I needed to get the OBXT running

- Finally drained oil to confirm what I think is bearing material.


Last night I decided to go ahead and drain the oil. There is no paste, no large chunks or anything. There is, however, super tiny shiny specs that can be seen when the oil is thinned under a light. I was expecting worse, but Im pretty sure what Im seeing is bearing material.


Spoke with my wife about the plan for it. Basically pitched it as we have 2 options. Take a 3-4k loss and walk away from it. Or put 4k into it to get it back on the road. She agreed that we should get it running. Then sell her 2.5i. I have 5 cars in the driveway right now and at least one needs to go before winter.


So we are back at square one. And Im downsizing the goals to a mild DD build. The plan in my head at the moment is a new OEM SB. Possibly with a vf52, depending on whether or not its advisable to just clean the old turbo and re-use.


And I have lots of holes in my shopping list at the moment and need to spend some time looking at other threads here to see what else I need to do while in there.


My list at the moment is:

- Shortblock

- Master gasket set

- Oil Pan (or clean old?)

- Oil pump

- Oil Pickup

- Oil Cooler

- Timing set

- Water pump

- turbo?


Im going to do some more research, but any suggestions or feedback is appreciated.

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