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Discussion Starter #1
Have a 2017 Impreza Hatch Limited in Island Blue. I was wondering what you guys think would be the best performance mods for our cars. I know most of them are still under development, and even then theres not a lot for our cars. If there is, which would you think would be the most significant/important?
 

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The engine is similar to that of the BRZ, right? So we could tune it and we could get 10-20 HP out of our cars. I'm not entirely sure of this, but there is definitely more in the engine. It feels like the car is sleeping until you literally floor the car. Hopefully, there are some more custom mods coming for our cars, but until then, custom solutions are the way to go. I am still going to wait for my warranty to expire though :) Cheers!
 

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The engine is similar to that of the BRZ, right? So we could tune it and we could get 10-20 HP out of our cars. I'm not entirely sure of this, but there is definitely more in the engine. It feels like the car is sleeping until you literally floor the car. Hopefully, there are some more custom mods coming for our cars, but until then, custom solutions are the way to go. I am still going to wait for my warranty to expire though :) Cheers!
Thats mainly why I asked. Its actually pretty quick when you floor it, but other than that its extremely sluggish. Im worried because our Imprezas arent very popular or desired like a WRX or STI, so theres not going to be much we can do in terms of performance mods because of limited parts. Thanks for the help!
 

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The Impreza is not designed for performance parts so you will never see anything available that will truly increase performance on a 152hp flat four. If you wanted performance, as CJ stated, you buy a different car. You may find what are called performance parts like intakes, etc. but they will only "look" good and make better "sound" but you won't feel or experience any difference in the drivability of the car.
 

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>The engine is similar to that of the BRZ

Yes, similar in all the ways that do not contribute to performance. The BRZ has higher compression, longer bore, shorter stroke, and different cams (higher redline).

Modify your car because you love it, because you want the look or sound, or because you can't stand having the "same" Impreza as anyone else....but don't mod the car for performance. It's hard enough to get performance from a NA engine, let alone one tuned for fuel economy.
 

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there are no tunes available for this NA engine. every reputable tuner I have contacted has told me they don't plan to even offer one for this car. I know on the Crosstrek forums there is a guy on there tuning the XV engines, which is very similar to ours, but even he isn't doing the 2018 XV yet. so I doubt we will see anything in way of a decent tune for quite a while, if ever. like the other guys said, if you want more power, trade up to another car. while I am happy with this car for what it is, I find if driven aggressively this car really comes to life without any mods. some people may not want to drive as spirited as I do, and I respect that, but I haven't felt like our Sport 5dr was lacking much for daily driving. I do not like cold air intakes at all. I have used them on numerous vehicles before and almost every single one was a waste of money and time. absolutely NO performance was gained. they look pretty under the hood but that is all. I have literally seen and heard of people sucking water in thru their intake and blowing their engine up. so I absolutely will not use one. if it was a race car, maybe, but not on a daily driven 4 cylinder. if you want it to sound good/better, take it to a muffler shop and have them swap the muffler. simple as that. cat back systems are a waste of money. mod it for you and do what makes you happy. but I wouldn't expect big gains if any from any of the mods available at this time.
 

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The engine is similar to that of the BRZ, right?
Well, similar in that they're both modern, flat 4's made by Subaru. No doubt there are many parts that are interchangeable - that's the Subaru way - but they are different engines according to Subaru. The BRZ and WRX both have FA20 engines, with the WRX turbocharged, obviously. Everything else in the Subaru line gets the FB20 or FB25 engine, or that flat 6 which I don't know much about.

So yeah, the FA and FB engines are more similar than different, but they have completely different heads and valve trains, for one thing. It'd be interesting to know if an FA20 head would bolt up to an FB20 block...

I've said it before, but I'll repeat it here: the Impreza Sport Hatch that I really want is one with the FA20 engine from the BRZ and the 6 speed transmission from the WRX. I don't want a WRX, so please don't condescend to recommending one; I'm not a teenage boy.

I don't really even want a ton of horsepower, I just want a responsive, free revving engine. The FA20 in the BRZ is not the most satisfying engine ever, but it can be a lot better than the FB20 in the Impreza. That and a 6 speed. Is that too much to ask for?
 

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I think the new Crosstrek is a 6spd manual trans.
 

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True CJ...you just can't get it to go any faster.
 

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@CJ...you are right. I forgot...you can lose weight:grin2:
 
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The engine is similar to that of the BRZ, right?
As others stated, the internals of the FA20 are quite different from the FB20. Also, the power delivery is very different. I have a 2013 BRZ, slightly modded (header, catback, tune, air filter) and I would not like this engine in a heavier car like our 2017 Impreza.

It's rev-happy, but also needs to rev to have some punch. There is very very little power under 2k rpm. My CVT on the Impreza regularly adjust engine speed below that when just keeping the speed. And the FA20's torque dip would feel worse on a heavier car with more mechanical losses like an AWD because the car will accelerate slower. To me, the FB20 is a better engine for a daily driver. Low-end torque delivery is better than the FA20 and it's what is used most on a daily driver. The FA20 shines above 4k rpm. For a sports car, that's cool. For a daily drive, less so.

Finally, most aftermarket bolt-on parts won't fit. The intake manifold is reversed on the BRZ. The throttle body is facing the front of the car, unlike every other Subaru. So a FA20 CAI or blower kit won't fit. The exhaust manifold is bent to the right (passenger side), where the FB20 is bent to the left (driver side) if I saw correctly. Any header won't fit.

You may get away with some light weight pulleys, but this is just money spent for nothing IMO.
 

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... The exhaust manifold is bent to the right (passenger side), where the FB20 is bent to the left (driver side) if I saw correctly. Any header won't fit.
All Subaru headers that I’ve found dump to the passenger side. Our Imprezas seem to be the only ones with a drivers side dump
 

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All Subaru headers that I’ve found dump to the passenger side. Our Imprezas seem to be the only ones with a drivers side dump
It may be a mistake on my part, but I'm pretty sure I saw the 1st cat on the driver side. That would be weird they changed it only on this model.

I did'nt find any pic of the undercarriage with an exhaust manifold on to confirm. I'll try to get a better look this weekend.
 

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First cat is on the drivers side. You won’t see the manifold in an undershot because of the aero-tray, it covers the entire engine bay.

Hard to see but this picture is behind the radiator looking to the drivers side.

 

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No the Impreza is not the only thing that routes down the driver's side. WRX routes driver side out of the turbo. Crosstrek and Impreza are both routed down the driver's side. I have a cheap header I saved from moving from my BRZ. I was contemplating about cutting the flanges off and flipping them and then routing a new exhaust so the 17 could have that UEL sound.
 

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Drive around in a 40 HP car for a bit then jump in the Impreza, it'll feel like a rocket ship.
My first car (in HS) was a 1976 Audi Fox, it had 79hp and was actually very zippy compared to all of my friends who had imports.
 
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