Build your own turbo kit?

[LimitedGT2.5]

Alright I can guarantee this has been covered before but I did search, and I kept coming up with the same posts, and are not very helpful at all....Alright my friend has a 99 outback and its getting up there in miles, he always wanted a turbo but not an excessive amount of money to buy a wrx and he loves his outback, and I told him I will not do the wiring for his swap if he did want to swap, I don't want to screw it up, lol, I did it on my 240sx no problem but subaru wiring=way different! Well I have been lurking around for awhile and have come up with some solutions. I was thinking his motor is going to need a rebuild (or at least head gaskets soon) and is it all possible to rebuild his ej25?? using sti parts-such as crank, rods, pistons, heads etc.....and use a wrx turbo manifold keep boost around 10psi no higher, using a E-manage and proper fuel management. Is this a good idea? Bad idea? Any input would be helpful....thanks guys.....I don't mind getting flamed-I'm a noob to Subaru's (I'm a Nissan guy-still looking for a 1991 turbo leggy though :smt002 )

[ScaryFatKidGT]

its a 2.5L right?

idk but if you changed the pistons and all that im pretty sure you would need a stand-alone manegment system and that takes some wiring i think it would be easyer to just do a swap and find someone that can do the wiring instead of basicaly doing a STi swap without the block

but i would suggest to just change the headgaskets maybe piston rings if you feel like ripping it apart and then put a wrx turbo kit on the stock motor at like 6-8psi

[xXGTBspecXx]

cough umm if you plan to turbo the existing 2.5 for cheap then check out this thread right here. it can help you out a lot.
viewtopic.php?f=22&t=12700 (http://www.sl-i.net/FORUM/viewtopic.php?f=22&t=12700)
that set to 6psi makes you faster then a stock wrx.
i really wouldnt just throw sti parts together in a EJ25D block and call it a day with 10 psi. to make it reliable i suggest you bring your boost down to say 5-6psi to be safe.

[impreza_GC8]

I run 11psi in an EJ25 Outback. It is running an EJ22T ('91-'93 Legacy turbo) ECU so some wiring is involved. Info about my car can be found here:
http://www.mysubarus.weebly.com

[rougeben83]

subachad uppipe and down pipe section + wrx td04 turbo (adjust wastegate arm all the way down, 7-8psi), stock wrx TMIC, wrx stock injectors w/ adapters or a 5th injector, use greddy emanage or rallitek's pp6 or JS knockguard/RRFR or some combination thereoff to get fuel.

At least that's the cheap way to do it. Go to rs25.com as a lot more 2.5RS guys have done homebrew turbo setups and they have documented it.

[Okin DaVanh]

subachad uppipe and down pipe section + wrx td04 turbo (adjust wastegate arm all the way down, 7-8psi), stock wrx TMIC, wrx stock injectors w/ adapters or a 5th injector, use greddy emanage or rallitek's pp6 or JS knockguard/RRFR or some combination thereoff to get fuel.

At least that's the cheap way to do it.

Can this also be done to the EJ22?

[rougeben83]

subachad uppipe and down pipe section + wrx td04 turbo (adjust wastegate arm all the way down, 7-8psi), stock wrx TMIC, wrx stock injectors w/ adapters or a 5th injector, use greddy emanage or rallitek's pp6 or JS knockguard/RRFR or some combination thereoff to get fuel.

At least that's the cheap way to do it.

Can this also be done to the EJ22?

The only thing that's usually complicated mechanical-wise with the ej22 is whether its single or dual port. However the subachad up/dp's were designed to retain the stock exhaust manifold location (ie you reuse your "y-pipe" manifold, or borla UELs that end up at the same spot) so that shouldn't be a problem.

Keep in mind, just like the ej25 na keeping the engine together relies heavliy on how safe your tune is and even keep in mind that you're still F/I'ing an engine that was not designed to take any amount of boost so you'll be reducing the lifespan of the engine as well...(usually what happens is one of the cyl. experiences lean condition or just goes from thousands of miles of detonation under boost).

[ScaryFatKidGT]

it shouldnt detonate at 6psi would it? running premium?

[rougeben83]

it shouldnt detonate at 6psi would it? running premium?

predetonation (ie knock, which will cause premature failure in any engine) and running higher cylinder temps from F/I, in an engine that was not designed to take such stress are two different things. You just to have to accept the fact that even with everything in the right conditions, you are going to be reducing the lifespan of an engine if you chose to make more power out of it than what was designed for from the factory. This applies to all engines. It's just a matter of how much longevity (from FOREVER to just 4years? 5years?) youre willing to sacrifice to wring out more power.

[LimitedGT2.5]

I run 11psi in an EJ25 Outback. It is running an EJ22T ('91-'93 Legacy turbo) ECU so some wiring is involved. Info about my car can be found here:
http://www.mysubarus.weebly.com
Alright how did you do your wiring? Do you have a link besides the one you sent me?

[jey]

Another option is to skip trying to build the NA block with STi bits and just get an EJ257 turbo short block to begin with. (Or some people swear by the "EJ22T" block too) There is more to the EJ257 than just the crank, rods, and pistons. If you start out with an EJ257 and use proper engine management you can get more than enough boost out of it before you start worrying about the transmission. The stock heads will bolt right up to the EJ257 block - that will save you some rewiring work.

[impreza_GC8]

I will vouch for Jey's method. I bought my car with the wiring already done and if it were up to me I would never have built an N/A block. When it comes down to it, in the back of my mind I know that I have an N/A block running more pressure than it was designed to and thats troublesome. I saw Jey's EJ251 setup in person and if I recall he was using his stock ECU and heads with a Forester XT intake manny and a WRX exhaust manny. It all worked quite well.

[rougeben83]

Another option is to skip trying to build the NA block with STi bits and just get an EJ257 turbo short block to begin with. (Or some people swear by the "EJ22T" block too) There is more to the EJ257 than just the crank, rods, and pistons. If you start out with an EJ257 and use proper engine management you can get more than enough boost out of it before you start worrying about the transmission. The stock heads will bolt right up to the EJ257 block - that will save you some rewiring work.

That's a great point you made. The sti shortblock NEW from Subaru costs about $1700; that's probably what youre going to be paying in parts alone just go get the lower comp pistons, polished crank, stiffer rods, etc to run in your N/A block for boost, and even then your block will still be based on one that was not intended to run boost.

The sti shortblock is probably the best value out there for subarus, both for na and turbo cars . I know a few WRX guys have gone to the sti shortblock instead of rebuilding their ej205 block because not only was it cheaper, or at the very least a better value, but they got the extra displacement as well - which is a great help in several aspects of running a boosted engine (torque off boost, faster turbo spool up, more power per psi of boost, etc.).

[jey]

I saw Jey's EJ251 setup in person and if I recall he was using his stock ECU and heads with a Forester XT intake manny and a WRX exhaust manny. It all worked quite well.

Actually, even more franken-motor than that - it's an NA Forester's intake manifold, only because my stock EJ22's intake manifold didn't bolt up to my EJ251 heads. If you use the WRX exhaust manifold, you will need to swap out the engine crossmember - it has a notch in it that allows it to clear.