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I know it's been done, but i am just curious as to what parts would be needed to do this.

I would love to go to a junk yard and look for a wrecked turbo Legacy or find a high mileage one that i can take apart for the parts. I would just want to know what parts would be necessary.

BTW, i have a 2001 RS if that helps
 

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New front crossmember. New front sway bar. New wiring harness, new ECU.
 

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You don't need a wiring harness or ecu. SubaChad has probably been doing this turbo setup the longest. He is always willing to help. Here is his website: Click
Kevin
 

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Im putting the Legacy turbo on my 2001 RS in the next month. I'll do a nice writeup about the install (although stimpy's and RS25.com are probably gonna be much better anyway). It really just bolts up to the existing EJ25, and the downpipe seems to be the only major holdup. Im gonna be running a J&S and a Spearco intercooler (maybe), as well as a Rising Rate Fuel Pressure Regulator. I think I should be fine @ 5psi, nothing too much.

Graham
 

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My understanding is that a custom downpipe has to be fabricated, but a local muffler shop could probably do it for cheap - like $100 or less - that was my plan.
 

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looks like fun fun silly willy =)

but i was wondering im i wasting money on NA stuff if i -MIGHT- get a turbo 2-3 years down the road?

or could i still keep like Cobb intake...and Stromung dual tip exhaust (if i got it?)
 

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RS25- Actually, a custom downpipe does NOT have to be fabricated. Scootr from i-club actually used an OEM WRX downpipe and it bolted up straight to his turbo. The only difference is doing this is that you have to use the WRX exhaust. I sourced both the downpipe and the cat-back (without the muffler) for $120! Thats a 2.25 inch exhaust. Only minor modifications have to be made to the mounting brackets on the exhaust for it to work. I talked to my local race shop and they wanted $500 for a stainless downpipe and mid-pipe. I still might go this route, but i'm not in favor spending lots of money on an exhaust. The WRX route is by far the cheapest, and works perfectly fine.

Snipes- If you plan on doing a turbo in the future, by all means start saving for it now, and don't go all out with the N/A stuff, although most of it will be turbo compatible (headers, cams, etc..).
Im actually using the Stromung myself, and I *think it should bolt up to the WRX exhaust, we'll just have to wait and see.
 

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So that just about completes my plans for the Legacy turbo kit, with that bit of info. The only other thing I am wondering about is the oil return line from the turbo. And TO the turbo. I read in "Maximum boost" that you should have no more than 25psi max going to the turbo or you can push oil past the seals, which causes smoking. You can limit the pressure, since I assume the oil pressure the engine puts out is closer to 50psi or more at full pressure.

Then the oil return line - I don't like the idea of gravity feed to the oil pan (and drilling into the pan) but am considering a sump under the turbo and then a little pump to pump it back to the valve cover or something...

Thoughts?
 

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James- Good thought with the sump, although I personally don't know anyone using that type of system to get the oil back to the pan. As far as tapping it, I guess thats up to the owner of the car. At first, I was gonna just use the banjo bolt setup on the bottom, but I don't see that as a feasible and safe way to return the oil to the pan. I don't know of anyone having problems with the tapped oil pan either, as I think the entire trip from the turbo to the pan is "south".

James have you sourced your lines for oil feed and return yet? If not, then paulnose on i-club can help you out. He's getting me both feed/return with all the fittings for a good price. I don't know about the 25psi limit going into the turbo, but im sure there is some sort of regulator to prevent excess oil pressure.

:flame:

Graham
 

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The thing I really wanted to do was some sort of an adapter to the dipstick tube. Ideally, I figured it would be a metal line that wrapped around the front or back of the engine. Then I would remove the dipstick tube and have a replacement made that had a T-fitting for the oil to return to the pan. I am really against the idea of drilling my pan, or otherwise removing it, because it is a HUGE pain.

The oil line that went to a banjo fitting into the drain bolt hole apparently was not the best solution either, but I am not quite sure why. It seems to me that it would have been the best solution. However, it was pretty messy to work with come oil change time. Andrew had one on his car and it just spilled oil everywhere when we took it off.

So I have not sourced any oil feed or return lines yet. As far as the 25 PSI, here's the quote:

Too much oil pressure can create problems with turbos. It is possible to force oil past oil seals that are in perfect condition if oil pressure exceeds 65 PSI to 70 PSI at the turbo. ... Problems of oil pressure overpowering the seal are evident in a frequent if not quite constant smoking problem."

Okay, so it seems I did not read it correctly - he also goes on to state (in a table)

Min Pressure:
Idle, hot : 5 PSI
Max load: 25 PSI

Min flow
Idle, hot: .1 Gal/min
Max load: .5 Gal/min

So that means you need LESS than 65-70 PSI and you're okay. Now that I've read that twice :) I am not worried. The Scooby puts out about 65 PSI at full RPM, right?
 

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*starts scribbling like mad on a notepad*
damn you people and your know-ladgeeeeyy stuff
 

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snipes said:
*starts scribbling like mad on a notepad*
damn you people and your know-ladgeeeeyy stuff
Ditto on that ! I want turbo ! I need to get all my questions on turbos resolved soon.
 

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James- Come to think of it, I don't think I know the max fuel pressure of our Subies. Im getting my OBD-II in the mail in the next few days, and i'll see if I can find it somewhere on there. You keep pulling up theses great ideas of where to return the oil from the turbo! The dip stick seems like it would work, although if using gravity feed, I don't know how well it would drain (unless of course you use the sump). As far as sourcing the lines, www.autocaresubaru.com has them, but they're kinda pricey and it is possible you could just assemble them yourself if you know enough about braided hoses.

Shoot away guys, they don't call these things forums for nothing.
;)


Graham
 

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Guys, the oil return line must go down. You can not make it take the scenic route to the dipstick. Tap the oil pan with a threaded fitting, no banjos. Just do it right the first time, you won't regret it.
Kevin
 

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Yes Kevin this would seem the most logical route. But, with using the oil pump to get the oil back to dipstick, it would work, although I am just not sure how necessary and efficient this would be. I need to have my pan tapped, could anyone possibly give me a ballpark of what it costs to do this? I imagine it can't be too much, its just a simple tap and weld.


Graham
 
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