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I would like to either supercharge or turbocharge an odb 2 ej22 from my 1997 Subaru Impreza wagon. However, I am not looking to gain high boost; I would like to see what I can do within the limits or parameters that the ecu would allow. How would it perform with bolt ons or a forced induction kit ( either by a turbo or a supercharger ) with simply assembling the required parts? Does it run similarly to a bugeye wrx or does it run like it would definitely need further tuning to refine it ? Can I still pass emissions with the stock ecu if it's equipped with the turbo? Sorry for anything I ask if it's been already answered or said in an old thread. I don't want to revive an old one needlessly and fresh/accurate/ accessible information is always nice for others to have at hand as some of the older ones may no longer have the supporting sources to answer any further questions.
 

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The car will run but will it run well, most likely not. N/A ecu is not mapped for forced induction and when you’re cramming more air than what the fuel maps can compensate for than you run the risk of running too lean which can potentially lead to detonation. The extra air will most likely cause a lean condition causing a CEL and depending on emission standards in your state you might not pass. It just doesn’t make sense to boost without a tune even if you were to limit it to wastegate pressure only because there’s a lot more that can go wrong in the long run because the engine won’t be happy. You’re paying more for the car to potentially run worse than what you have stock right now which makes the power gain from installing a forced induction kit to not be worth it. Spend the extra money and make sure you have a reasonably reliable car.
 

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It was once said somewhere on here "Every time a vape bro wrecks a GD, a GC gets its wings!" This is for many reasons, but one of them is the best way to boost a first gen is to swap it. You can usually find a decently running WRX that was in a side or rear end collision for 1500-3000, so by the time you go buy a turbo and figure out exhaust and intercooler etc etc etc... you can just rip all the guts out of a WRX and it all fits like legos. Go to iWire for the wiring merge and bingo, boosted first gen without too much hassle! After I parted my donor WRX I gave my shell to a a rally racer so it could live another life before it gets crushed 🙌
 

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So, I have a different opinion. It can be done. It can be done well. And it can be done safely. EJ222 (Phase II MAP 2.2l) / ej251 Turbo Conversion Parts List | Subaru Impreza GC8 & RS Forum & Community (rs25.com)
I have a 2003 impreza wagon (ej251). I also have been looking into it. From everything I have seen stock wrx parts + 5psi limiter + map clamp + walboro 255 = Reliable power, probably close to early stock wrx. Compression is too high, and timing is too aggressive to run much more than 5psi without a tune.
There is a facebook group called "NA/T Subarus" it is an amazing resource. Has everything you need to know, just have to do some searching. Good Luck. I begin the process next summer after I finish college.
 

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So, I have a different opinion. It can be done. It can be done well. And it can be done safely. EJ222 (Phase II MAP 2.2l) / ej251 Turbo Conversion Parts List | Subaru Impreza GC8 & RS Forum & Community (rs25.com)
I have a 2003 impreza wagon (ej251). I also have been looking into it. From everything I have seen stock wrx parts + 5psi limiter + map clamp + walboro 255 = Reliable power, probably close to early stock wrx. Compression is too high, and timing is too aggressive to run much more than 5psi without a tune.
There is a facebook group called "NA/T Subarus" it is an amazing resource. Has everything you need to know, just have to do some searching. Good Luck. I begin the process next summer after I finish college.
You are correct, I didn't mean to be confrontational when I claimed doing a full WRX swap is the best option. Doing a swap worked well for me and it has worked for many others, but that doesn't mean you can't make a solid car out of a NA/T subaru, in particular if you keep the boost low, like you said. I can't speak from experience about an NA/T build, but I can speak from experience about the WRX swap. After doing a lot of research also I chose to do a full swap after finding a suitable donor, and I'm very happy with the results. I think the best option is to go with an engine and engine management setup that was designed to handle boost. My swap is tuned for about 12psi and feels like a very rowdy little monster. At the end of the day it seems like the NA/T path would require a lot of money to boost it for 5psi and being capped there, vs putting down similar power with OEM parts and room to grow with mods and a tune.
 

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I got about 12-15k in debt trying to turbocharge these cars the "wrong way" which is the way you're wanting to move forward with. Heed my "No." Terry blew up a shit ton of motors doing it this way too.

Matching the power of a 2 liter WRX at 5psi is boring. Beating Audis, Maseratis, and BMWs at 13psi is a heckin blast. Trust us, 5psi is okay, but I will guarantee that you'll want more, then you need to do it the right way any how.

Yes it is possible but it's not worth the hassle when doing it the correct way is just as easy and yields far far FAR better results.
 

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2000 Impreza 2.5RS BRP
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I would highly recommend simply swapping the car with an EJ205 Copart donor. As far as technical reasons, having the car in boost will definitely confuse the ECU so that even in the best case you'll struggle to pass emissions with it.

I have nothing but respect for those that do turbocharge their stock engines while running a piggyback or voltage clamp on the stock ECU. I don't think many people would deny that's the harder road vs. a one and done up front effort.

It was once said somewhere on here "Every time a vape bro wrecks a GD, a GC gets its wings!"
I didn't exactly say it anywhere, I just made it my signature so everyone was forced to read it :D
 

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1998 forester L ej25d
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I swapped heads with an ej25d and made a junk yard ej22d and turboed it and have both a greddy blue and ultimate. I'm about 3.5k (2020/2021 prices) in that's only parts some suspension, brakes and better tires/wheels it's been all my labor and I have a shit ton of tools, and experience. It's done and ive been driving at 8psi now for a few a miles but I'm chasing a cam seal leak right now other than that it took about a week to build the engine and get it in my 98 foz.. it's been fun but it's not done yet still haven't even tuned. Installed my meth kit and I'll be going with a remote turbo drain pump since my set up is tight, it drains well now but I want to go remote anyway to make sure it drains properly.

Also I'm running a stock ej25 ecu and haven't got my wideband in yet so I don't know afr right now but it will run on a stock ecu pretty decently.

The point I'm trying to make is that it'll cost you a bunch of money and time. I did consider a swap but sourcing an engine with known history and finding the correct harness but I figured it would be a wash in the end and it was easier for me with what I already had to go this way. Good luck all I can say is the pop pop and the turbo spool was worth it for me :devilish:
 

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There's a whole Thread on here on boosting the NA-T and their lifespan: NA-T Longevity Thread

I also have done it on '96 Legacy, and this sounds like what you're (initially) after: 1996 Legacy L Turbocharged

My AFR's have always been fine @ 5-7 PSI.

Main challenge w/yours - IMHO- is that you have the single-port exhaust ports on that engine, which makes it more difficult to just 'bolt-on' the dual-port turbo exhaust manifold.
 
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