Boxer Tech Turbo Build

My buddy has a 04 FXT that started running higher than normal temps and instead of selling it the car, he bought a new STI short block for it and is building that to ensure its long term reliability.

 

That being said, I'm planning on buying his EJ257 short block to rebuild it. This is going to be for my blue 99 Outback, dubbed thee Land Shark by my wife. It'll be my own little Super Gramps.

 

My budget for this build is $2,000 for the motor and goal is ~275 HP. By sourcing good used WRX/STI take off parts, I am sure I can achieve that target number. More like I better not exceed that budget because my wife will end that sh!t real quick. I am going to use my EJ25D heads because I heard they're probably the best flowing heads next to the EJ20X heads.

 

So far, here is my build list. Feel free to chime in on what I should/shouldn't be looking at.

 

- 04 EJ257 Short Block (stock internals)

- 04 WRX transmission, rear end, and axles (considering swapping in RA gears)

- 99 EJ25D heads

- EJ20R intake

- STI TMI

- WRX Crossmember

- STI headers, up pipe, and down pipe.

- VF39 turbo

 

At the moment, I am unsure on the injectors, looking into different ECU options, and I'm probably missing a few more things

i'm no forester expert but isn't the 04 FXT short block a ej255, and never recived the STI treatment with the different ej257 pistons which would have had a different piston dish.

 

i believe the pistons (and top compression ring gap) to be the only thing different from a ej255 to ej257. unless there is something special about the 04 forester short block that makes it different which i'm sure there is since you posted it and you definitely know what you are doing since i follow your posts pretty frequently.

 

so are you getting his new sti block your buddy just bought?

The LGT and Forester XT are both Ej255 which is only minorly different then the ej257 but I couldn't tell you exactly how they're different. I looked into buying a blown up LGT and putting in a new ej257 long block and it'd have been a direct plug and play deal. If you're working with a 255 or 257, I'd just use the heads from that motor, I don't think the much older 25D heads will supply you with any benefits, and if anything, may cause more headache in the future since you'd have to run a different intake to accommodate the intake ports. Plus you'd have to modify the 25D heads to accommodate the little cam driven unit that sits on the back of the passenger side head which is found of turbo cars (PS I have no idea what it does)

i'm no forester expert but isn't the 04 FXT short block a ej255, and never recived the STI treatment with the different ej257 pistons which would have had a different piston dish.

 

i believe the pistons (and top compression ring gap) to be the only thing different from a ej255 to ej257. unless there is something special about the 04 forester short block that makes it different which i'm sure there is since you posted it and you definitely know what you are doing since i follow your posts pretty frequently.

 

so are you getting his new sti block your buddy just bought?

 

No I'm buying up his old block. 04/05 FXT and the 05/06 LGT/OBXT use the same block as the 04-06 STI. If you look up the part number for the short block on Subaru parts, the fitment is the same. Here is the part number: 10103AC030

 

The LGT and Forester XT are both Ej255 which is only minorly different then the ej257 but I couldn't tell you exactly how they're different. I looked into buying a blown up LGT and putting in a new ej257 long block and it'd have been a direct plug and play deal. If you're working with a 255 or 257, I'd just use the heads from that motor, I don't think the much older 25D heads will supply you with any benefits, and if anything, may cause more headache in the future since you'd have to run a different intake to accommodate the intake ports. Plus you'd have to modify the 25D heads to accommodate the little cam driven unit that sits on the back of the passenger side head which is found of turbo cars (PS I have no idea what it does)

 

The only thing that makes the FXT and LGT/OBXT differ from the STI mechanically is the external stuff like the exhaust, intercooler, and turbo. Electronically, the STI has a more aggressive ECU tuning, that's it. Subaru called it the motor in anything other than the STI the EJ255, but it's a wolf in sheep's wool. In 06, the FXT and WRX got the same motor, with the OBXT and LGT following suit the next year in 07. But for some reason, the STI guys want to believe their special when the reality is, Subaru made an unofficial STI version of the Forester and Legacy/Outback in the US with no one knowing.

 

The 257/25D combo has been done, so I'm just replicating the research done here: http://www.rs25.com/forums/f145/t170500-frankenstein-ej257-block-ej25d-4-cam-heads-turboed-insane.html

The only difference between ej255 and ej257 shortblock are pistons( if i remember correctly the difference is the dish size), which changes compression ratio, either way they are interchangeable.

The only difference between ej255 and ej257 shortblock are pistons, which changes compression ratio, either way they are interchangeable.

 

For the 06+ EJ255, that statement is true. For the 04/05, every single individual part number from the rotating assembly, to the heads, to even the sodium filled valves are identical to the EJ257. It was marketing and the first time that Subaru had brought a 2.5L Turbo motor to the US, so naturally and rightly so, they wanted people to buy the STI over the other cars, since it marked that nameplates debut in the US as well.

 

See this thread: https://legacygt.com/forums/showthread.php/05-06-lgts-255-04-06-stis-257-once-and-264989.html

 

It shows everything is the same.

the 05-06 lgt, and 04-06 sti have same longblock basically, its called an ej257 in the sti and ej255 in the gt, after that everything started using the ej257 shortblock, the heads varied, but the shortblock was the same. She shortblock which is just the engine block and rotating assembly. Whats confuses most people is the shortblock and longblock terminology. For general purposes the ej255 and ej257 labeling applies to everything outside the shortblock really.

 

Both shortblocks in the ej255 and 257 are stamped with just EJ25, so it would be almost impossible to distinguish an ej257 shortblock from a ej257 shortblock unless you measured the piston dish size. And I'm pretty sure after 06 they all started using the ej257 shortblock. Basically every EJ25 is interchangeable with an EJ257 or EJ255, doesn't matter what car wrx, sti, legacy , xt. They all have ej25's, and even though there is some slight difference between ej25's, it seems after 06 they simply just went to a different piston.

 

The most important factor are the heads. If you go to a dealership and order a shortblock they will ship you an EJ25 with the "ej257 pistons" even if you had a block with "ej255" pistons. Its the same shit!

 

And now I'm more confused than before.... this ej255 ej257 discussion is the worst..... there is a whole lot of terminology which applies to the word ej255 and ej257, one cars ej257 will not be the same for other model cars with an ej257. Intake manifolds, turbo setups, intercoolers, the terms 255 anad 257 are so loosely applied it makes it a nightmare. EJ255/EJ257 shortblock, longblock, complete engine.... its Subarus fault.

When it comes to parts, and engine designs, subaru is an absolute shit show.... you don't know what's inside your block until you actually open it and look at part numbers, especially for the early 2.0's and 2.5's.... They use the whatevers on the shelf or in stock method to build. Either way I wouldn't worry that much......

When it comes to parts, and engine designs, subaru is an absolute shit show.... you don't know what's inside your block until you actually open it and look at part numbers, especially for the early 2.0's and 2.5's.... They use the whatevers on the shelf or in stock method to build. Either way I wouldn't worry that much......

 

I plan on tearing the motor down to it's two halves so that I can send the halves and the heads off to the machine shop to get hot tanked and decked.

 

I just scored a free set of STI yellow injectors from a buddy of mine, so I am going to send those off for cleaning and to be flow tested.

 

I am debating whether to run my stock EJ25D intake manifold or to track down an early twin-turbo manifold for the longer runners. I have a complete set of coil on plugs that I am going to use, so the height of the intake doesn't matter as much.

 

I just ordered a Speeduino kit from WTM Tronics. This is going to be a great test of this standalone ECU. I'm learning as much as I can because I am looking into becoming a distributor for them. For <$200, it's a deal that I can't pass up.

I picked up the short block today.

 

 

Its a little dirty but the deck is not warped and everything looks great. No indications of abnormal cylinder wear and the rods are nice and tight.

The parts collection is progressing a lot faster than I anticipated. Here is what I have coming:

 

04 WRX Subframe

Turbo header

Catless downpipe

 

Still looking for a STI intercooler system. My buddy has a FXT intercooler, but I am not sold on it. He also has a TD04 with a little shaft play and a B16G with no shaft play. Not sure which one I want to go with yet. He wants $50 for the TD04 and $100 for the B16G.

At that price point, go big!

At that price point, go big!

 

I will, I was unsure if that B16G would actually bolt on to a Subaru up-pipe and use the same downpipe. I'm a little short on available cash at the moment until my wife gets her first paycheck after returning to work after the summer. It's been hard with one income because she was short her summer stipend due to maternity leave. She only got $1,200 for 8 weeks of pay instead of $4,000 so it was a challenge paying bills this summer and doing fun things like build my cars.