Can you Turbo a 2.5l 6gen legacy?

Hey guys and gals!

 

I'm new to this forum and I've been lurking so much information since I bought my '17 legacy last month. (pearl white I love it) I've been doing research on turbo kits for this vehicle and can't seem to find one. I, however, did read on this forum that a custom turbo kit can be used on the car but then someone else was mentioning that the "pressure ratios" of the engine were off or something to that effect. I'm new to cars so I know what a piston does and how an engine works but I'm still learning the semantics. I'd appreciate any guidance on this matter as I am trying to compete with my friend who has one of the newer Honda Accords with the turbo 1.5l and he keeps whooping my butt even though I have a whole liter on him

I'll be the first to say it - should have bought another car if you wanted to go fast. While you can bolt some custom made turbo kit onto your car (see ~5k bill to do correctly unless you're a fabricator yourself, in which case knock a couple grand off), you'll run into the issue of tuning the car. Running anything beyond a tiny bit of boost will nuke a naturally aspirated motor with the stock tune. There are no tuning options for the 6th gen NA cars' ECU that I'm aware of, because why would there be. So, expect to spend another several thousand dollars to get a standalone engine management system into the car, and be ready to end up with a bunch of the features your car came with to likely be disabled in the process. By the time all that's said and done, you could have gone and bought a car that came set up the way you want from the factory.

XRT has tuned the 6th Gyn 2.5i, so I suspect it is possible to tune a turbo on the stock engine. The CVT is the real issue. If you want to go faster, buy a different car.

pshaw...OP do it. it'll be fun. It'll be like buying a well used 4th gen...a money pit.

 

 

Making your current car faster by adding a turbo kit, especially with the "glass" cvt is asking for heartache and an empty wallet. Especially if you are new to Subarus. Alot of other options for go-fast for alot less money

Should have bought a WRX if you wanted to race Hondas.. The CVT can't handle that much power.. Cobb tuning has tried tuning a Turbo Forester and Wrx and it won't even hokd there Stage 2 Kit without blowing the CVT..[emoji17][emoji17]

 

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You can do it. I keep it low boost and see how the trans react to it. Imagine a little T25 mounted in there (sleeper).

 

So how are the STI with the CVT trans?

Edited September 23, 2021 by amusa

The STI doesn't come with a cvt. Also the issue is which CVT you have in this case. The 2.5i comes with the TR580 which is rated lower than the TR690 in the WRX and 3.6R. I know the TR690 will hold 300 hp no problem, but beyond that I have no experience. As for the TR580....I wouldn't try it ...

 

 

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I know someone who has a CVT in there STI.

In the US? Are you sure they are not driving a WRX they slapped an STI badge on?

 

Don't be fooled by the upgraded CVT shift knob that says STI in the WRX. Our 2020 CVT WRX came with an STI knob. It was definitely not an STI.

Edited September 23, 2021 by DougKelly20

He had it imported here in the US. He said it was a limited production made and said something about A4 or was it S4. I can’t remember. Edited September 24, 2021 by amusa

I googled S4 STI and came up with a WRX S4 STI Sport #, which is WRX with STI parts or it could be a WRX S4 tS STI. tS is usually trim and springs. Either way both of those combinations had the CVT with the FA20DIT motor used in the WRX.

 

As already mentioned about the 2.5i has CVT transmission with a lower torque rating than the WRX/FXT/Ascent/OBXT/LXT with the HTCVT. The tuners have already found that they are having issue with the HTCVT in those with simple mods. The 2.5i will fare worse with its CVT.