opinions on coldair intake on '11 Impreza?

Discussion in 'Modifications & DIY how-to' started by g1nkgo, Feb 13, 2012.

  1. g1nkgo

    g1nkgo Member

    Ive got a 2011 impreza that i like alot, but wouldnt mind having a little more power. ive been reading up on cold air intakes. anyone have any opinions? think it would help out? thanks
     
  2. Sparta

    Sparta Active Member

    Look into a high flow k&n drop in filter first. The stock air box is pretty efficient from the factory and alot of aftermarket intakes hurt the car rather than help it.
     
  3. g1nkgo

    g1nkgo Member

    filter

    awesome thanks. ill check that out. you have any other ideas on how i can help it out a little?
     
  4. Jake

    Jake Active Member

    cobb flash or cobb protune maybe even a downpipe
     
    Last edited: Feb 13, 2012
  5. talos

    talos Member

    if youre looking for more power intake exhaust and tuning are clearly your first resorts but imo, just as much fun can be had from some sway bars and springs. just depends on how you like to drive.
     
  6. Jake

    Jake Active Member

    as stated by sparta, don't waste your money on an intake until you're ~400hp. and yeah, these cars benefit a LOT from suspension mods. makes driving fun
     
  7. rsutton1223

    rsutton1223 Obsessed Supporting Member

    I wouldn't even bother with the K&N on the '11's. If you are going to get a CAI...you need to tune for it.

    Are you running an Imprezza or a WRX or a STI? The answers above are specific to the turbo versions of the car mainly. If you are running a NA Imprezza...it's not the same issues.
     
  8. Matt

    Matt Think before you post Staff Member Supporting Member

    He doesn't have a WRX. he's got a 2.5i Impreza. None of what you've mentioned will help him, except the panel filter.
     
  9. RSConvert

    RSConvert ɹǝuɹnʇpɐǝɥ uʞnɟɐɥnɯ ɐ sʇı Supporting Member

    WRX swap it.
     
  10. g1nkgo

    g1nkgo Member

    yeah im in an Impreza 2.5. Theres lots of info out there on wrx/sti, but im trying to sift thru it to see what would help my car out. im not trying to make it a wrx, just a little more acceleration would be nice.
    theres no tuning for an engine thats not turbo, right?
     
  11. Sparta

    Sparta Active Member

    Ohhh


    Suspension then.
     
  12. BlackAndBlue

    BlackAndBlue Member

    there is but you probably wont need to
     
  13. Mad Mallard

    Mad Mallard the mad mallard

    you can tune any engine.

    from what I understand, the tuning on a turbo for power is more straight forward because you're using the turbo to create atmospheric conditions you want to get more power and can adjust it accordingly.


    if you have a non-turbo car, you have to pretty much work with the atmosphere the rest of the world does, and instead increase fuel and increase compression. increasing fuel doesn't cost too much comparatively, but running higher compression gets expensive quickly, and usually involves premium93 gas only.
     
  14. rsutton1223

    rsutton1223 Obsessed Supporting Member


    Correct. But the comments above are in relation to the fact that it can be harmful for Subaru turbo motors to add an intake without a tune because of how they interact with the MAF.
     
  15. Berzerklo

    Berzerklo Active Member

    Here is a good write up from a Legacy forum I am on, where he talks about upgrades for a 2005 2.5i Legacy wagon: http://legacygt.com/forums/showthread.php/2005-2-5i-wagon-report-various-upgrades-179164.html

    A 2005 Legacy 2.5i wagon is similar to your car in a lot of ways though. There really is not much you can do to get that much more power out of the 2.5i. Suspension and mount upgrades will help everything work more efficiently. A drop-in air filter will help too (but as people have said... a cold air intake will not do too much for you in terms of power gains for $). Do you have a manual or an automatic? You could look into a short shifter if you have a manual, and that would decrease time between shifts and just make it a more enjoyable drive.

    The only other option that may work for you is a throttle controller. It does not make your engine produce any more horsepower, but you can alter the responsiveness of the engine. These cars are all drive by wire (DBW) now, so there is no cable between your gas pedal and the throttle body. The gas pedal is just a sensor that tells your throttle how much to open or close. With a controller you can change the gas pedal input to throttle position relationship... basically making your car react faster (so you could have your throttle go to WOT with a 10-15% pedal depression). It may kill your gas mileage, but it could also make your car seem a little faster. This is kinda similar to the SI system on some of the turbo subies. I have done zero research on it, but it may be worth looking into. There seem to be a few options out there, but here is just one I found:
    http://www.proimporttuners.com/parts/2011-subaru/impreza-apexi-smart-accel-throttle-controller.html

    Good luck!
     
  16. Jake

    Jake Active Member

    great info here
     
  17. bixs

    bixs Supporting Member

    did you read it all?


    I've seen controllers that claim to improve response in DBW systems which improve latency of the system, those are cool. The DBW on the GR STI's at least, is controlled by a table in the ECU. So as he said, you can have it go WOT at like 70% as the STI does in s# mode. It won't reduce gas mileage unless you don't understand how to adjust your foot when you are driving around town, aka driver mod.


    Keep in mind, you can make the car fun with suspension and stuff..maybe a tiny bit more fun with engine stuff, but you should ultimately consider looking at wrx's
     
  18. g1nkgo

    g1nkgo Member

    awesome. thats the kind of thing im looking for. im sure someday ill be looking at a wrx, but its not in the cards right now. honestly i'm surprised at how much i'm liking the impreza- its definitely a better drive than other <200hp cars that i drove. if it had a little more pick up at start id probably be happy keeping it for a while.

    i was told that better plugs and wires would probably help, but ive never really seen a difference in my past cars, though ive mostly driven trucks and suvs. think that stuff would help?
     
  19. rsutton1223

    rsutton1223 Obsessed Supporting Member

    Even if they did help, I can't see it being enough that you would actually notice in driving. Use that money on things like swaybars and other handling mods. You'll have a lot more fun with the car that way. There isn't much you can do in terms of power, so it will be about making the power you do have fun.
     
  20. g1nkgo

    g1nkgo Member

    thanks again for the info. ill probably just forget about the engine stuff and maybe work on suspension, sway bars, maybe some lighter wheels.
     
  21. g1nkgo

    g1nkgo Member

    thanks. i ended up picking up a k&n filter but i had another question.

    would there be any reason for me to get a hood w scoop? remember im driving a plain old impreza hatchback, so im never going to be a wrx. i just like the style and if it can give me a little better performance id be interested. thanks. feel free to yell at me for buying a 2.5 too. ha.
     
  22. Jake

    Jake Active Member

    don't see it increasing performance whatsoever. i know on the older imprezas everything was rubber booted/etc. im assuming the electricals on the newer ones are the same way, but you wouldn't want rain and such just dumping on top of the motor. im assuming there are some guys who have done it to aid in engine cooling, maybe there is a shroud (piece that goes underneath the scoop) to redirect water and aid in cooling
     
  23. g1nkgo

    g1nkgo Member

    ahh crap, that makes sense.
     
  24. Jake

    Jake Active Member

    yep, because the turbo vehicles have the intercoolers underneath the scoops and shrouds in between to direct air/rain directly into the intercooler and therefore out the bottom and off the top of the transmission/out the bottom of the car. if that intercooler isnt there rain will just blow all around the engine bay
     
  25. b reel

    b reel Active Member

    build up the suspension and be happy. NA power is the wiser choice, less shit to worry about.
     
  26. g1nkgo

    g1nkgo Member

    thanks b reel. you thinking sway bars and what else? maybe a better exhaust?
     
  27. b reel

    b reel Active Member

    sways, bushings, struts/springs or coil-overs, light weight wheels.

    wouldn't try all this cool big wheel zero wheel gap BS. bigger wheels/tires means more weight and drag and completely pointless unless you have the power to take advantage it.
     
  28. g1nkgo

    g1nkgo Member

    yeah, it came with 16s, so ill probably stick with that. i found some motegi 16" that were about 15 lbs. im assuming thats less than the wheels that come on the car.
    the only time i would address the struts/springs/coilovers is to lower the car, right? i like places with crappy roads, so im alittle afraid of lowering the car. just makes me nervous.

    i appreciate the help. this is the first time ive had a car that i could do some work to. the sites definitely been helpful.
     
  29. Jake

    Jake Active Member

    don't buy coilovers if you just DD your car. coilovers are meant for track cars, or if you want to dump your car and don't care about ride quality. there are some good quality 'cheaper' coilovers (BC, Megan, etc) that would be great for DD/autocross/mountains/spirited driving. otherwise, a good set of koni adjustable shocks and some lowering springs (any name brand but tein are great for subaru really) will really make you happy.

    but yeah, sways, steering rack bushings, and various other odds and ends to stiffen the chassis (after spring/shocks) are cheap and when added one at a time will greatly increase your driving happiness every other paycheck or so.
     
  30. b reel

    b reel Active Member

  31. Berzerklo

    Berzerklo Active Member

    I think Short throw shifters are well worth the small investment as well!
     

Share This Page