Wouldn't GT components on a 2.5i be cheap?

[burnout8488]

Okay, I fully understand that trading up to a GT is the most logical thing for a 2.5i owner to do when they want to turbocharge their car. I support this, and I laugh when people think they can do it better.

 

But really?

 

I've been thinking, and browsing the classifieds seeing all of these cheap GT stock leftovers nobody wants. Headers, uppipes, you name it, dirt cheap. Uppipe for 30 bucks, downpipe for under 100 bucks. If you fell into the right deals, I bet you could get the entire exhaust and a DECENT stock turbo for under $500.

 

Now, if you DON'T have aspirations to make GT power levels out of it, why couldn't all of this be bolted up and ran at low psi (stock wastegate pressure)? No intercooler nonsense, just a straight pipe to the throttlebody, and some ducting to the airbox. Get a tactrix cable, and call it a day. Actually, wouldn't an old WRX intercooler fit?

 

Am I missing something here? Okay, you'd have to notch the subframe for the uppipe, yes. That's free if you've got the tools already. Various oil and coolant lines need to be ran, but that's just a handful of fittings and hoses, nothing you couldn't figure out on a weekend for under 50 bucks.

 

Noones even tried this before on a 4th gen Legacy, have they?

[FLlegacy]

From what I have gathered on this forum and on a forester forum, there isn't much aftermarket support in the way of tuning for such a mod on the N/A models, there is a thread on here that is turbo-ing an N/A '05 outback. After all is said and done if you could get all the parts to fit and working how they are supposed to you would still be faced with the daunting task of having the ecm and pcm tuned for a turbo engine they weren't meant to run. At the least you would need an accessport or other piggyback and a professional tune which pushes the cost wayyy up.

 

Your reasoning sounds good but in reality it isn't as easy as adding parts and calling it a day, if it were it would be done and being sold in a kit already. Also if most are like me, I need my car to get me places reliably so I would much rather leave it alone and buy a turbo when I can afford it especially with a factory warranty.

[TSiWRX]

Can a mod please compile/merge this thread with the one below?

 

http://legacygt.com/forums/showthread.php/possiblei-145823.html?t=145823&highlight=turbo

 

Also, might want to cross-link this thread:

 

http://legacygt.com/forums/showthread.php/needed-tune-2005-legacy-2-5i-145556.html

 

FWIW, this kind of thing is sparking my interest.

 

We've now seen some fun swaps and pretty damned impressive upgrades on the 2.5GT...what about the 2.5i side of things? Let's not shoot down every idea.

 

After all, we're an enthusiast community - this kind of thing is bound to be fun (of the cursing and bleeding knuckles kind, of course....)!

 

---

 

On the topic of turbocharging the N/As, I remember this AVO/Rallitek collaboration:

 

http://forums.nasioc.com/forums/showthread.php?t=646130

 

And I thought there was a bolt-on/plug-and-play supercharger system available to, no?

[burnout8488]

The thing is though, there ARE definitions available for certain years of 2.5i cars. It could definitely be tuned on a budget if you're one of the lucky ones that have a compatible ECM. You wouldn't need an Accessport, a VAG-COM or tactrix cable is all you'd need. Cheap.

 

I think this method would be a great way to get 40 or 50 extra hp (Maybe more? BASE wastegate boost) and still remain somewhat reliable. My car has 105,000mi, I'm not concerned about underhood aesthetics at all, nor do I want a car with an external wastegate, or loud exhaust. If this was possible for 500-700 dollars it'd be a no brainer. 99% of the parts would be OEM Subaru anyway, and we already know the N/A EJ25 is capable of safely handling a little extra power. Nothing about this kit would be 'aggressive,' not the tune, not the boost.

[burnout8488]

TSi+WRX: Absolutely. The 2.5i is really starting to get a lot of love around here, and this type of turbo kit is the most logical IMO. Most of the GT guys scrap the parts that we could easily bolt up.

 

Its only a matter of time before almost all of the 2.5i romraider definitions are available, then pretty much anyone should be able to tune, N/A OR turbo swapped.

[sulk]

Its only a matter of time before almost all of the 2.5i romraider definitions are available, then pretty much anyone should be able to tune, N/A OR turbo swapped.

 

The only problem with the definitions, is if I recall correctly, the guy who was making them got hired by cobb (or whoever makes the accessport), and has stopped making them altogether.

 

It doesn't seem like anyone else has decided to pick up the slack since then.

 

There was a group buy going on for tunes on nasioc (link here) that included NA's, but I dont know if it went anywhere, doesn't seem like it. GEE-OTTO and Ianb were on it, but I think if they had a tune we may of heard from them.

[burnout8488]

Iamb just managed to get experimental definitions for his car from someone on romraider forums. I'm surprised, but i think it really is going somewhere. Check a recent thread in the tuning forum for this.

[TSiWRX]

^

 

 

Also, might want to cross-link this thread:

 

http://legacygt.com/forums/showthread.php/needed-tune-2005-legacy-2-5i-145556.html

 

 

I'll again reiterate the need for a mod to somehow compile these threads into one official "Sticky" or something of the like.

[burnout8488]

Agreed, these questions are cropping up more often lately and having everything compiled would be great.

[FLlegacy]

For reliability sake a professional tune with a shop that has good and reputable experience with subaru would be a must. No way I would trust my car to a few definitions from ROMRaider and me at the helm. Your 05 may be a lucky one, so far as I can tell there is nothing for 2007 yet, and your 5mt is going to make it that much easier. I am not saying it can't be done or that it wouldn't be a great mod, I am just not seeing it being cheaper or less of a PITA than trading for an LGT at this point anyway.

 

If you can do it I would love to see the build-up and how-to for it. You could also look into a forester xt or wrx stock turbo, I have seen some for sale for fairly cheap. I agree with you about the parts bein cheap enough. For those like me though, that don't have a serious performance tuning shop within a reasonable distance that could still be a limiting factor in what I would be willing to do. Also my warranty isnt up for 4 more years and 58k more miles.

 

Best of luck if you are going to try it out. Keep us updated if you do.

[burnout8488]

Oh, it'd definitely be a PITA, but yes, definitely cheaper than the GT route still.

 

For tuning I was thinking the e-tune route would be the only way to stay in budget. $150-200 bucks and infamous1 can work his magic. You'd need a wideband O2 for a safe datalog though to get the best tune possible out of it, its not like this is a very common swap.

 

If I start this, I think i'm going to make a pile of parts over the course of a year or so. Nothing I'm going to jump into quickly, but if something falls into my hands for cheap, I'll buy it.

[CTATV]

I still say if it could be done for 700 dollars you should ask yourself have you done suspension and brakes first... if you havent then its still not worth it yet

[FLlegacy]

And what is so special about the lgt suspension and brakes? The Lgt owners are ditching their stock stuff as far as sway bars and links go, so what is the difference in that regard. That upgrade isn't specific to the 2.5i. Stopping can easily be helped by a good set of aftermarket pads ( assuming the rotors are in good shape and are true).

 

Noone on here is talking massive amounts of boost just something to give a little more oomph to the 2.5i. I can't imagine 50-75 Hp more over stock taxing the brakes and suspension that much.

[CTATV]

And what is so special about the lgt suspension and brakes? The Lgt owners are ditching their stock stuff as far as sway bars and links go, so what is the difference in that regard. That upgrade isn't specific to the 2.5i. Stopping can easily be helped by a good set of aftermarket pads ( assuming the rotors are in good shape and are true).

 

Noone on here is talking massive amounts of boost just something to give a little more oomph to the 2.5i. I can't imagine 50-75 Hp more over stock taxing the brakes and suspension that much.

 

Nothing is special about the LGT suspension and brakes. I'm saying you should upgrade your regular legacy with aftermarket brake and suspension options before you spend any money on more power... I have a stage3 LGT and still say the best money I spent was on my BC coilovers and Hawk HPS brake pads..

[burnout8488]

Yeah, all said and done I wouldn't expect my budget turbo setup to even be as fast as a stock LGT. It might happen if you're lucky, but it's not like the stock suspension and brakes are going to be dangerously taxed. It wont even come close. Most of the 2.5i guys that'd consider this probably already have some sort of mild modifications anyway, like myself.

 

As it stands right now, i don't even have enough power to overwork the suspension on my car right now. JDM RSB, sway bar bushings f&r, and Hawk pads are the extent of my modifications. Along with my Yokohamas, I'm extremely pleased with the way my car NEVER breaks loose.

 

I do agree with you CTATV, but I think it's a more applicable philosophy when going from stage0 --> 1 or 2 on a GT. That's when the power becomes enough to make a stock height LGT sloppy when the rear wheels feel some boost

[CTATV]

While I understand what your saying, honestly power only is a consideration for driveablility a small part of the time. Everybody turns and stops and enhancing the ability to do those is separate from power in my humble opinion.

[TSiWRX]

So, towards that end, here's my questions/concerns:

 

What are the differences between the 2.5GT and 2.5i/i Limited models, specifically in terms of the suspension components?

 

^ I'm truly ignorant of this, and would love a good breakdown. And yes, I read the FAQ, but it doesn't provide me with much more detail, to be honest.....

 

The brakes are rather easy to cite - the '05 brochure lists the 2.5i with 10.8 inch fronts and 10.6 inch rears, with the Limited models increasing to 11.5 fronts. The GT models all came with 12.3 fronts and 11.3 rears - the reason why the GT models needed 17-inch wheels.

 

My main concern from this difference in braking hardware would be whether or not the ABS/EBD systems would be calibrated differently between the two vehicles, and whether if there are any other hardware-based differences (master cylinder?).

 

There's only a listed 100 to 190 lbs. difference in curb-weight between the farthest apart of the i versus GT models (increasing that margin to a full. 200 lbs if counting the wagon variants, too). Why such a big increase, seemingly, in brake hardware, for so little weight disparity?

 

Certainly, there's a difference in the rubber shod around the wheels, too.

 

FWIW, I am also among those who think that chassis upgrades to the non-turbocharged models are where you'll see the best bang-for-the-buck returns...but at the same time, I'm really interested to see how far both tuning can take the N/A, as well as what can be achieved with both a "stock parts 'swap' (obviously, it'll be more involved than that)" as well as with aftermarket bolt-on kits.

[burnout8488]

The suspension differences are very subtle. IIRC, the rear sway is 15mm 2.5i, 16mm GT. Front is 20/21, respectively. Struts and springs are identical.

 

Given that the GT guys complain about the mushy brake pedal and lack of stopping power just as much as I do, I'm inclined to believe that the master cylinder is the same. I'm glad I got the limited, but i don't think I have any improved bite over the 10.8" guys (thats what she said?) due to the rest of the system sucking.

[FLlegacy]

Nothing is special about the LGT suspension and brakes. I'm saying you should upgrade your regular legacy with aftermarket brake and suspension options before you spend any money on more power... I have a stage3 LGT and still say the best money I spent was on my BC coilovers and Hawk HPS brake pads..

 

So brake pad swap and we are good to go? If you have ever driven a 2.5i you would know that the braking is excellent, and the handling is fairly good as well. I don't see why I would want to go farther into those things before I knew what I could get out of the engine. You can always adjust your foot to what the car can handle and if you can't then you shouldn't be driving period.

 

But we are still just discussing a theoretical DIY turbo job, no harm in that, talking isn't going to make a car faster or more powerful... if only it could...lol

 

edit: mushy pedal must be something with the older subies mine is pretty firm and if i really press it my car stops quick, fast, and in hurry. I have 48k on the stock pads and rotors. The yokohamas are long gone though.

 

I can understand upgrading the chassis but honestly straight line acceleration is where the 2.5i needs help it gets around corners as good as anything in its class, but at the stop light it gets eaten up by anything more substantial than a geo metro... ok not that bad but close.

[2005legacy2.5i]

Agreed, these questions are cropping up more often lately and having everything compiled would be great.

 

I was just thinking about that today!

[f1anatic]

What I would be interested in is developing a small bolt-on supercharger kit for the NA cars. And when I say small supercharger kit - something with up to 4-5 psi . There are small superchargers for cars of 1 L displacement on the asian market. And then there are superchargers for motorcycles.

[GEE-OTTO]

The problem is that the the VF40 and 46 don't have a low enough min BOOST you need a small turbo like a VF 22 or one that has a really low min Boost. And then the cross member

[GEE-OTTO]

What I would be interested in is developing a small bolt-on supercharger kit for the NA cars. And when I say small supercharger kit - something with up to 4-5 psi . There are small superchargers for cars of 1 L displacement on the asian market. And then there are superchargers for motorcycles.

 

That has been made Raptor Superchargers they make a MAF kit for 06+ and MAP kits for 98-2005

[burnout8488]

The problem is that the the VF40 and 46 don't have a low enough min BOOST you need a small turbo like a VF 22 or one that has a really low min Boost. And then the cross member

 

I was wondering this but didn't think to research it yet. Do you know what those figures are on say, a VF40 running just wastegate boost? Would a smaller turbo be able to bolt up to the legacy GT up pipe and down pipe?

 

Anything with less boost is better here, because it increases the chance that the car can use the stock injectors once properly tuned. 30-40hp with no lag would be a nice cheap kick in the pants.

[toreadorranger]

So brake pad swap and we are good to go? If you have ever driven a 2.5i you would know that the braking is excellent, and the handling is fairly good as well. I don't see why I would want to go farther into those things before I knew what I could get out of the engine. You can always adjust your foot to what the car can handle and if you can't then you shouldn't be driving period.

 

I dont know what car your driving but my stock GT handled like crap. You must have a vastly different idea of what good handling is.