NA to turbo and 5mt to 6mt swap

[Kukazula]

Hey y'all.

 

ive got a NA 5mt 2.5i. Shes past 300k miles and starting to show some wear. But shes mine and i love her... I gotta keep her alive.

 

I've always wanted a gt, but they arent easy to find here. I am mechanically skilled, i understand it will be expensive and time consuming. That being said-

 

I want to drop in a 2.5 turbo and a 6mt.

 

What will i need and what can i salvage from the 2.5i?

 

Thanks in advance,

-kuka

[Notorious]

I would really reconsider this choice if I were you. It would be much easier and far cheaper to find a clean GT and ship it across the country than to swap both the engine and the transmission. The main things you can salvage from the 2.5i is the body shell and interior. Even if yours are in pristine condition at 300k miles, I wouldn’t go through with this.

[Scruit]

Just buy a GT. I've been on both sides of this decision. Just buy a GT.

[Kukazula]

Thats my problem. I cant just buy a gt. I live in rural Montana, ive looked but cant seem to find one in my area that isnt scrap. Shipping is outrageously expensive.

 

I have a backup car. I know it will take a long time and a lot of work but im up to it.

 

I have a friend that owns a salvage yard. He has an 07 sti with 27k miles on it. Some little old lady had it as a garage filler. Thing got tboned pretty bad but im pretty sure most everything important survived.

 

Could i just do a straight swap from the 07 sti into my 05 legacy?

[dgoodhue]

Thats my problem. I cant just buy a gt. I live in rural Montana, ive looked but cant seem to find one in my area that isnt scrap. Shipping is outrageously expensive.

 

I have a backup car. I know it will take a long time and a lot of work but im up to it.

 

I have a friend that owns a salvage yard. He has an 07 sti with 27k miles on it. Some little old lady had it as a garage filler. Thing got tboned pretty bad but im pretty sure most everything important survived.

 

Could i just do a straight swap from the 07 sti into my 05 legacy?

 

If you think $1000 to ship car is outrageously expensive, then this isn't the project for you. Investing a bunch of money and labor into 300k+ miles 2.5i is throwing good money at a bad idea. Many of the STI part will bolt into your Legacy, but your going to need a bunch of parts from a GT to complete the swap and their is going to be A LOT of wiring involved. You probably need a LGT parts to cars as well. If you want to do STI Legacy, just buy a GT or better yet a Spec.b with the 6MT. If your getting a good deal on the STI you can sell the parts you don't need.

[A. Daigh]

I can definitely be done! However, (from personal experience) swapping into a 300k mile car is where I would do some more thinking. These guys are right, you are going to need pretty much everything off the LGT such as crossmembers (turbo and non-turbo are different to clear exhaust) steering rack, possibly hubs, axles, Wiring, modules, hood, (if going that route.)paint? body work? So you need two donor cars if you want to do it as cheap as possible. Now you are going to have a ton of money and time and two cars into a body of a car that is falling apart (window frames leaking at highway speeds/body panels rusting out.) So do some thinking! if you absolutely love the 2.5i then it can be done, it's just going to take a lot more time and money than finding a neglected LGT. Check MT craigslist. There are a few LGTs on there. Also saw a wrecked LGT with no engine on helena craigslist for like $850 Hope this helps!

[Notorious]

How comfortable are you with wiring and wiring diagrams? It’s not a simple swap as just inserting the engine and transmission. You will need a shaft from an automatic Legacy GT and a lot of other parts from a Legacy GT to make the 07 STI transmission work. Let alone all the wiring to make the EJ257 work. Wiring harnesses need to be split, ECU needs to be swapped as well with either one from the STI or a Legacy GT. Plus you’ll need to wire up the DCCD controller. It’s much easier to swap in a full Spec B transmission.

 

With enough time and money, anything can be done. It’s up to you if it’s worth it or not. Much easier and cheaper to find a Legacy GT and either travel to it or ship it home. I drove my Legacy GT over 5 hours home and I never regretted it. I also had a 2.5i before in an Impreza but with head gasket issues. Sure I could’ve swapped a WRX motor in there but it was never logical or worth it to me, I still miss that car but the GT is much better.

[Scruit]

It can be done, yes. If you approach this as a PROJECT car, not a daily driver, then it could be a fun project. You may be blazing a new trail in a lot of respects, and you will need electronics and wiring skills as well as physical mechanical skills.

 

 

For comaprison... If my 5mt eats poop today, I'm putting a replacement 5mt in it. Once my Golf R arrives, and my LGT is my winter beater, a busted 5mt would probably get replaced with a 6mt just for the fun an experience in a project car. But NOT because it's a worthwhile project for a daily driver.

 

 

That other car will be your primary vehicle for a long time. And I double-dog dare you to set a deadline... :-) A project like this is a strange beast, and timelines cannot be set in stone, but instead in smoke.

 

 

 

"If you want to hear God laugh, tell him about your plans for the future..."

 

 

 

 

If you truly are doing this as a project thing then go for it, I applaud you. Sounds like a fun project. If you are doing this to save money or hassle, buy a GT.

[Somac]

You will spend five times what your Legacy is worth trying to swap it with an EJ255 and 6MT when you can just buy a spec.B for less. If you're willing to spend that much money and can't find one near you, save up for a plane ticket and fly out to buy one from somewhere else.

[EatingInternet]

Grab some more hours at work and pay the troll toll. Finance if you can't afford the lump sum. Don't reinvent the wheel.

[Kukazula]

So heres the plan:

 

The sti im picking up is coming to me for 500 bucks.

 

Shipping costs for a working gt to my door are around 9800 bucks... Maybe I'm looking in the wrong place.

 

Anyway... Ive got a place lined up off my property as to not cause storage and space issues. Basically a storage win it with a full set of tools, engine hoist, mount, tranny mount... The whole nine yards. I can use it as long as i need to.

 

Im going to gather the parts I need, store them in the shop, and as far as ecu goes im probably going to do an aftermarket unit such as a haltech.

 

I am aware that this will take me 5x longer than I intend

I have done similar things before.

 

I am proficient with wiring... I've done all the work to my car since i bought it. Clutches in my garage and the whole bit.

 

Car is in immaculate shape. No rust, no body damage other than a bumper scrape. Interior is clean and unmolested.

 

My questions are:

 

What combination of parts from what vehicles would i need to fit an sti motor and 6mt into a 2.5i legacy?

 

Is there a specific combination of transmissions/diffs that offer the best fit and ease of install?

 

I know this will be hard but I feel i should make it as easy as possible.

 

What driveshafts/ hubs/ suspension/ mounts/ etc etc do i need?

 

I already know i will need bigger rims for the brakes. Got a set of 17x7's at the powdercoating shop now. Test fit on the sti confirmed the clearance.

 

Thank you all for your feedback

[dgoodhue]

$500 is really cheap for 27k miles STI parts car, it seems like your missing a 0 on that price. Either the seller is an idiot or the car is stolen. I would highly recommend running a carfax on the VIN to make sure you not setting yourself up for legal issues.

 

No one is going to walk you how to do your swap, most likely your the only one doing this exact swap. Get a factory service manual. Do the research on 2.5i to GT engine swaps. Research on using STI parts on a GT. Their is a 6MT STI swap thread, read that. Their are STI brake swaps threads. etc.

 

I would recommend doing the engine, wiring, & ECM swap 1st before doing all the easier documented mods incase you have issues or get overwhelmed with the STI engine swap.

[A. Daigh]

Dang! $500 is a steal for that donor car. I remember when I did mine, I got an 06 wrx with 32k that had been rolled for like $4500 or something. As dgoodhue said, there's a lot of info out there you just have to do your research. Once again I would highly recommend finding a GT donor car as well so you aren't trying to source all the GT parts individually. I would look for an auto one so you have the driveshaft.

[ehsnils]

Thats my problem. I cant just buy a gt. I live in rural Montana, ive looked but cant seem to find one in my area that isnt scrap. Shipping is outrageously expensive.

 

I have a backup car. I know it will take a long time and a lot of work but im up to it.

 

I have a friend that owns a salvage yard. He has an 07 sti with 27k miles on it. Some little old lady had it as a garage filler. Thing got tboned pretty bad but im pretty sure most everything important survived.

 

Could i just do a straight swap from the 07 sti into my 05 legacy?

If you pick a lot of the electrical from the sti and run that piggy-back on the legacy you kight make it work. It might be easier than the frank_ster build with a buick engine in a Legacy.

 

 

If you consider to take the gearbox from the sti, also take the rear diff. The sti transmission is better than the stock legacy 2.5i transmission anyway.

 

 

You better take the whole sti as a donor car since there's always going to be a new part you need for this. And a bulkload of time and patience.

 

 

Just read this thread before you start: https://legacygt.com/forums/showthread.php?t=140053

[Kukazula]

So what I'm gathering is,

 

I can swap the sti's 2.5 turbo, rear diff, (maybe driveshaft?) and 6mt into the legacy if I take as much of the wiring harness as possible, get a lgt crossmember and automatic tranny driveshaft, with a little work I could rework the pigtails at the wiring harness connector sites, add a few wires here and there for extra sensors and whatnot, use the sti's ecu (will put in aftermarket .edu eventually) to run it all... Correct?

 

And of course ill need to swap the hubs and calipers over.

 

I do have a silver lgt hood to match mine off a gutted lgt from the same yard. Might run a front mount while im in there anyway.

 

if a front mount is installed, would it be possible to buy or fabricate a ram air intake off the hood scoop, to keep it functional? Would that even be plausible or worth while? I know I should probably just focus on the big stuff but hey, its a fun idea to roll around for now.

 

Also I will be getting an aftermarket billet aluminum radiator. Has some extra plugs for things like turbo cooling lines. Should be oil lines on the turbo to the engine from the factory.

 

And for those of you wondering... It is no longer my daily driver.

[Darth SpecB]

I doubt an intake would fit on top of the engine. Besides there's a lot of heat soak in that area so the fender area is your best bet. I believe someone said you will need an lgt front cross member, and lgt driveshaft for rear diff. There is someone I think his name is code who did an sti drive train swap on his lgt. Look up that thread for much info. And good luck, I'm looking forward to this!

 

Sent from my SM-G950U using Tapatalk

[A. Daigh]

This should be a fun project! Here's Just another idea or possibility for you since it's going to be a fun build car not so much a daily or a wife pleaser...Have you thought about swapping the dash? I know people think STI dash is a downgrade from 05+legacy. I ended up doing this in my 02 outback because I liked the center mounted tach and it actually made the swap really damn easy. Pretty much plug n play other than wiring in the door locks, window switches, wipers, fuel level sensor and pump, headlights and all that. You will have to modify the dash beam slightly but it pretty much bolts right in other than the glovebox area. Oh, and swap some HVAC parts as well (cant remember specifically) but it all works out in the end and is cleaner than you would think. Be prepared to have a small gap on either side (about an inch) due to the STI being slightly narrower than the Legacy. You can hardly notice it though. I would run the STI modules anyway because the car will be mostly STI. I wouldn't even consider a standalone or any of that. If you want to keep the Legacy dash you can still run the STI harness like you were thinking, you'll just have to wire in all the dash functions also.

[Kukazula]

@Darth SpecB

 

Dont get too excited. I wont be doing the work till august when I have access to a full shop with a lift. I will however provide updates when possible and document anything interesting for posterity.

 

@A Daigh

 

I like the idea, however I am going to stick with my current set up. I have the dual hvac system and I have an android powered head unit running in the dash. Its hooked to the obd, a back up camera, the stereo... And a few other things. It was quite a project, easily 30 hours of wiring because of the sheer number of wires, running and installing new components, unforseen problems and testing because my Chinese instructions were so detailed and great, not to mention the dual hvac complicates things.

 

I see your profile says bozeman mt. (Stalker level 1000)

I was born and raised there. Living in butte currently for some godforsaken reason. We'll have to hook up sometime and 'mire each others rides, eh?

[Kukazula]

Update time for the legacy project.

 

Just got my trade degree in welding and acquired a few things to go along with that.

 

Also just had a eg33 dropped off and a 6mt.

 

I'm gonna rebuild the engine, twin turbo it, and fabricate anything I could possibly need.

 

New thread will be starting soon as soon as I evaluate the engine and make a list of questions regarding problems I forsee, for example mounting the engine in that bay and what cross member etc.

 

I know it's ridiculous, I know it's gonna be difficult and I know it's gonna be spendy. Save it... I already know. See you all on the flip side.

[Guest]

$500 for that STI is not legit, or the seller is indeed an idiot.

 

The swap would be relatively straightforward except electrical. Your best best is to get entire LGT wiring harness and ECU and BIU, as well as immobilizer, else you'll need dealer to marry the whole thing.

 

I expect you can run into gauge cluster issues, but maybe not, it may just work.

 

EDIT: So it's H6 & turbo swap....? Oh, good luck. Can be done, but that's totally custom project. You'll need standalone ECU.

[rougeben83]

Sti trans is pretty straightforward, you need an 08-14 STI shift linkage, and a 05-09 Legacy 4 speed auto driveshaft (5speed auto is too short, 5 speed manual is too long -ask me how I know). You'll need matching rear diff - if you're sticking to the r180 off the STI, you'll need rear axles from a spec B, if you want to keep the axles, you'll need to change the ring/pinion gear on the R160 to match your 6 speed's - you'll end up with a weaker VLSD or open rear diff though. You can leave the DCCD wiring off and the 6speed will run in the default torque split, depending on year.

 

The sti engine will also bolt in, engine mounts the same, pretty much all stock locations the same on the 2.5i. Electrical wiring and harness merge will take up the bulk of your time.

 

If you're going the supergramps route, just be sure to spend the extra $$ on engine management and tuning. I'm sure you've seen the MCM vids, but make sure you review them at least 4 times to see exactly what they did to make that swap happen.

[Max Capacity]

Guy's read what he said, that's where most of his parts are coming from...

 

 

 

 

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I have a friend that owns a salvage yard. He has an 07 sti with 27k miles on it. Some little old lady had it as a garage filler. Thing got tboned pretty bad but im pretty sure most everything important survived.

[Kukazula]

Yeah it's an h6 build now. I just said screw it, if I'm gonna do it I may aswell go for gold.

 

I'm scrapping what I can from the impreza and selling the rest. The engine was indeed in good condition and I got 4k out of it. More project money.... Up here in Montana Subarus are very popular and I've already got people lining up for the rest of the parts.

 

Like I said, I'll post a new thread once I get some time to get my poop in a group.

 

And the STI was 500 bucks because I know who owns the yard and they paid 350 for it. It's good to have friends... He bought a 2019 STI navy blue "gentleman's package" this year off the lot though so I don't know if we can be friends anymore, but I'll still take his help.

 

You guys are super helpful, and I thank all of you for your information.

[Kukazula]

Yeah it's an h6 build now. I just said screw it, if I'm gonna do it I may aswell go for gold.

 

I'm scrapping what I can from the impreza and selling the rest. The engine was indeed in good condition and I got 4k out of it. More project money.... Up here in Montana Subarus are very popular and I've already got people lining up for the rest of the parts.

 

Like I said, I'll post a new thread once I get some time to get my poop in a group.

 

You guys are super helpful, and I thank all of you for your information.