Welcome to the North American Subaru Impreza Owners Club Thursday August 28, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 06-29-2010, 02:59 PM   #1
imprezajohn
Scooby Newbie
 
Member#: 249752
Join Date: Jun 2010
Chapter/Region: RMIC
Location: Pueblo West, Colorado
Vehicle:
2010 Impreza 2.5i
silver

Default New, new, new

Ok, This is my first Subaru, I've spent many, many years in the American Muscle Car world and my understanding of these vehicles is pretty much zero. With that being said, what are, if any, the first N/A performance mods folks do to these vehicles? I drive 160 miles a day round trip to work, so reliability and gas mileage are an issue. Any help will be appreciated. Thanks.
* Registered users of the site do not see these ads.
imprezajohn is offline   Reply With Quote
Old 06-29-2010, 04:17 PM   #2
Henry H
Scooby Newbie
 
Member#: 184330
Join Date: Jul 2008
Location: Southern California
Vehicle:
2008 Impreza 2.5i
Dark Grey Metallic

Default

If you're looking for muscle, the N/A isn't where you'll find it. There ARE performance parts but its not worth it for the little gains you'd get out of it. Any safe mods are modest at best without beefing up internals, going with forced induction and plenty o tuning.

Tuning is a big deal but yet again N/A imprezas' have limits.

Just be glad you got a reliable AWD daily driver that won't get stuck in the snow like the jerk in that accord in front of you when you hit the slopes. I was that jerk once
Henry H is offline   Reply With Quote
Old 06-29-2010, 05:02 PM   #3
GEE-OTTO
Scooby Specialist
 
Member#: 201277
Join Date: Jan 2009
Chapter/Region: MAIC
Location: Arlington VA
Vehicle:
2009 Legacy GT
OBP

Default

Quote:
Originally Posted by imprezajohn View Post
Ok, This is my first Subaru, I've spent many, many years in the American Muscle Car world and my understanding of these vehicles is pretty much zero. With that being said, what are, if any, the first N/A performance mods folks do to these vehicles? I drive 160 miles a day round trip to work, so reliability and gas mileage are an issue. Any help will be appreciated. Thanks.



YOu chose the wrong car my friend should have stayed with whatever muscle you had the 2.5i offers NONE
GEE-OTTO is offline   Reply With Quote
Old 06-29-2010, 05:47 PM   #4
Audi20Tdriver
Scooby Newbie
 
Member#: 206040
Join Date: Mar 2009
Location: Carlsbad, CA
Vehicle:
2009 Audi A4 2.0T
APR Stage 1

Default

seriously, when I was in CO everyone had a subaru or an Audi.. I was in heaven because I still had my 2nd subaru at the time. You can search around the N/A thread for performance stuff.. It's fun to mod cars, yes.. but you will never get real performance from the 2.5i, the WRX and STi are the performance versions of the impreza.. Think V6 mustang compared to GT or cobra.. it's a great daily driver though.. just enjoy it for that man..
Audi20Tdriver is offline   Reply With Quote
Old 06-29-2010, 07:45 PM   #5
chazly413
Scooby Specialist
 
Member#: 151079
Join Date: Jun 2007
Chapter/Region: MAIC
Location: College Park, MD
Vehicle:
2005 2.5RS RBP
motec system exhaust-RIP

Default

You can look at cams, headers, and a tune to get you around stock WRX levels. Beyond that, you're looking at much more extensive modification.

You should still do headers (a good equal length, **** the sound, power is what counts) as that will give you your largest bolt on performance gain. Then, go crazy with handling mods.
chazly413 is offline   Reply With Quote
Old 06-30-2010, 03:38 AM   #6
Audi20Tdriver
Scooby Newbie
 
Member#: 206040
Join Date: Mar 2009
Location: Carlsbad, CA
Vehicle:
2009 Audi A4 2.0T
APR Stage 1

Default

Quote:
Originally Posted by chazly413 View Post
You can look at cams, headers, and a tune to get you around stock WRX levels. Beyond that, you're looking at much more extensive modification.

You should still do headers (a good equal length, **** the sound, power is what counts) as that will give you your largest bolt on performance gain. Then, go crazy with handling mods.
dude, you are out of your mind. I agree about upgrading the suspension but cams headers and a tune will not put a 2010 2.5i anywhere near a 2010 WRX or an 09, 8 7 6... you get the point. Do you realize a new WRX has 265 HP and is faster then the 2008 or so STi?
Audi20Tdriver is offline   Reply With Quote
Old 06-30-2010, 08:32 AM   #7
GEE-OTTO
Scooby Specialist
 
Member#: 201277
Join Date: Jan 2009
Chapter/Region: MAIC
Location: Arlington VA
Vehicle:
2009 Legacy GT
OBP

Default

Quote:
Originally Posted by chazly413 View Post
You can look at cams, headers, and a tune to get you around stock WRX levels. Beyond that, you're looking at much more extensive modification.

You should still do headers (a good equal length, **** the sound, power is what counts) as that will give you your largest bolt on performance gain. Then, go crazy with handling mods.
Really it is that easy man i better get those rallitek cams, oh and that TWE EL header and get it tuned by EFI

OP do not listen to posts of the above variety YOU WILL NEVER GET CLOSE TO WRX numbers with cams headers and a tune you might get 150 at the wheels and that is an exaggeration. The sounds is your choice EL or UEL it really doesnt matter you cant take more air out of an engine that the intake valves allow in on the exhaust stroke.


The only big power N/A wise you might make is from a EZ30R or a EZ36R now those two platforms have real potential. Anyway trade your 2.5i for a WRX or a Legacy GT or a STi or an older RS and swap it.


But in the mean time get suspension parts
GEE-OTTO is offline   Reply With Quote
Old 06-30-2010, 09:27 AM   #8
b4wantab
Scooby Specialist
 
Member#: 21293
Join Date: Jul 2002
Chapter/Region: MWSOC
Location: Oak Park, IL
Vehicle:
05 OB Black Bean
1969 W-30

Default

Do muffler and maybe headers.

Hope you kept the old heavy iron for weekends.

Peace,

Greg
b4wantab is offline   Reply With Quote
Old 06-30-2010, 10:35 AM   #9
chazly413
Scooby Specialist
 
Member#: 151079
Join Date: Jun 2007
Chapter/Region: MAIC
Location: College Park, MD
Vehicle:
2005 2.5RS RBP
motec system exhaust-RIP

Default

Quote:
Originally Posted by GEE-OTTO View Post
Really it is that easy man i better get those rallitek cams, oh and that TWE EL header and get it tuned by EFI

OP do not listen to posts of the above variety YOU WILL NEVER GET CLOSE TO WRX numbers with cams headers and a tune you might get 150 at the wheels and that is an exaggeration. The sounds is your choice EL or UEL it really doesnt matter you cant take more air out of an engine that the intake valves allow in on the exhaust stroke.


The only big power N/A wise you might make is from a EZ30R or a EZ36R now those two platforms have real potential. Anyway trade your 2.5i for a WRX or a Legacy GT or a STi or an older RS and swap it.


But in the mean time get suspension parts
I'm talking 08 wrx and under, probably should have clarified that. I also said near, as in 200-210 crank. It is so easy to get 40 whp from cams, headers, and a tune.

EDIT:
40whp may be a stretch, but definitely 30. Either way, I'd still do headers.

Last edited by chazly413; 06-30-2010 at 12:09 PM.
chazly413 is offline   Reply With Quote
Old 06-30-2010, 12:06 PM   #10
razrielle
Scooby Specialist
 
Member#: 205698
Join Date: Mar 2009
Chapter/Region: MWSOC
Location: Wichita, KS
Default

Suspension mods are the best bang for buck deal you can get with our cars. for sound I have the magnaflow 2.5" wrx catbacks on my car
I would save your money by not getting an accessport and learning how to tune and use opensource

Edit: Also from what I hear is you can get better gas mileage from tuning it too, our stock tunes are crap
razrielle is offline   Reply With Quote
Old 06-30-2010, 12:13 PM   #11
Henry H
Scooby Newbie
 
Member#: 184330
Join Date: Jul 2008
Location: Southern California
Vehicle:
2008 Impreza 2.5i
Dark Grey Metallic

Default

Quote:
Originally Posted by razrielle View Post
Also from what I hear is you can get better gas mileage from tuning it too, our stock tunes are crap
Is that so? I'll have to look into that. Any links on this?
Henry H is offline   Reply With Quote
Old 06-30-2010, 12:19 PM   #12
razrielle
Scooby Specialist
 
Member#: 205698
Join Date: Mar 2009
Chapter/Region: MWSOC
Location: Wichita, KS
Default

Quote:
Originally Posted by Henry H View Post
Is that so? I'll have to look into that. Any links on this?
Ill have to do some digging, I might have seen it in the EM section
razrielle is offline   Reply With Quote
Old 06-30-2010, 02:26 PM   #13
Audi20Tdriver
Scooby Newbie
 
Member#: 206040
Join Date: Mar 2009
Location: Carlsbad, CA
Vehicle:
2009 Audi A4 2.0T
APR Stage 1

Default

Quote:
Originally Posted by chazly413 View Post
I'm talking 08 wrx and under, probably should have clarified that. I also said near, as in 200-210 crank. It is so easy to get 40 whp from cams, headers, and a tune.

EDIT:
40whp may be a stretch, but definitely 30. Either way, I'd still do headers.
bro.. you are still out of your mind. first of all, once you start playing with the cams.. the daily smooth drivability is compromised depending upon how aggressive the grind is. It would be absolutely stupid to buy a new 2010 and do such aggressive modifications to a daily driver.

secondly, there is a 54 HP difference between a stock 2.5i and 08 wrx and the weight difference is only 70 pounds.. a highly modified N/A RS coupe maybe in auto X.. but sedans and wagons vs sedans and wagons.. why even bother..
Audi20Tdriver is offline   Reply With Quote
Old 06-30-2010, 03:12 PM   #14
GEE-OTTO
Scooby Specialist
 
Member#: 201277
Join Date: Jan 2009
Chapter/Region: MAIC
Location: Arlington VA
Vehicle:
2009 Legacy GT
OBP

Default

Quote:
Originally Posted by chazly413 View Post
I'm talking 08 wrx and under, probably should have clarified that. I also said near, as in 200-210 crank. It is so easy to get 40 whp from cams, headers, and a tune.

EDIT:
40whp may be a stretch, but definitely 30. Either way, I'd still do headers.
Try again 200 crank NOT happening LOL even with cams and headers. Header go ahead they make track pipes that will mate it up but youll get the CEL either way you go.
GEE-OTTO is offline   Reply With Quote
Old 06-30-2010, 03:43 PM   #15
chazly413
Scooby Specialist
 
Member#: 151079
Join Date: Jun 2007
Chapter/Region: MAIC
Location: College Park, MD
Vehicle:
2005 2.5RS RBP
motec system exhaust-RIP

Default

Definitely 30 from just cams, headers and an intake. No tune even:

http://forums.nasioc.com/forums/showthread.php?t=595740
chazly413 is offline   Reply With Quote
Old 06-30-2010, 04:19 PM   #16
GEE-OTTO
Scooby Specialist
 
Member#: 201277
Join Date: Jan 2009
Chapter/Region: MAIC
Location: Arlington VA
Vehicle:
2009 Legacy GT
OBP

Default

Quote:
Originally Posted by chazly413 View Post
Definitely 30 from just cams, headers and an intake. No tune even:

http://forums.nasioc.com/forums/showthread.php?t=595740

Thats on a EJ251 different engine different timing maps plus he had CAI, CBE, Headers, and cams not ot mention he is comparing that EJ251 to a EJ205!!!


EJ253 vs EJ255 youre not getting close period.
GEE-OTTO is offline   Reply With Quote
Old 06-30-2010, 04:30 PM   #17
Audi20Tdriver
Scooby Newbie
 
Member#: 206040
Join Date: Mar 2009
Location: Carlsbad, CA
Vehicle:
2009 Audi A4 2.0T
APR Stage 1

Default

yea dude, I was part of that thread.. that is apples to oranges. Actually everything you are mentioning is apples to oranges. What is the point on heavily modifying a brand new car for the OP, and having a super lumpy idle and a loud track oriented car to drive long daily drives to work.. just to almost be like a bone stock old model WRX? It's cool for a build but what you propose is just not intelligent. Not to mention that old wrx with like a 5 minute laptop tweak could pack on another 40HP with no supporting bolt ons..
Audi20Tdriver is offline   Reply With Quote
Old 06-30-2010, 04:42 PM   #18
Cuddles
Scooby Newbie
 
Member#: 161077
Join Date: Oct 2007
Chapter/Region: MAIC
Location: RIP Christy Mack
Default

Quote:
Originally Posted by razrielle View Post
Suspension mods are the best bang for buck deal you can get with our cars. for sound I have the magnaflow 2.5" wrx catbacks on my car
YouTube- New exhaust
I would save your money by not getting an accessport and learning how to tune and use opensource

Edit: Also from what I hear is you can get better gas mileage from tuning it too, our stock tunes are crap
Woa. I have the same exhaust, I think...but (no offense) yours sounds awkward. Maybe it's the camera. Check it:

Cuddles is offline   Reply With Quote
Old 06-30-2010, 05:46 PM   #19
chazly413
Scooby Specialist
 
Member#: 151079
Join Date: Jun 2007
Chapter/Region: MAIC
Location: College Park, MD
Vehicle:
2005 2.5RS RBP
motec system exhaust-RIP

Default

Quote:
Originally Posted by Audi20Tdriver View Post
yea dude, I was part of that thread.. that is apples to oranges. Actually everything you are mentioning is apples to oranges. What is the point on heavily modifying a brand new car for the OP, and having a super lumpy idle and a loud track oriented car to drive long daily drives to work.. just to almost be like a bone stock old model WRX? It's cool for a build but what you propose is just not intelligent. Not to mention that old wrx with like a 5 minute laptop tweak could pack on another 40HP with no supporting bolt ons..
It's not gonna be super lumpy. These aren't 9k rpm race cams.
chazly413 is offline   Reply With Quote
Old 06-30-2010, 06:45 PM   #20
RaceFaceXC
NASIOC Supporter
 
Member#: 165749
Join Date: Dec 2007
Chapter/Region: South East
Location: stupid Florida
Vehicle:
2007 No YELLING
on the bus!

Default

Quote:
Originally Posted by Henry H View Post
Is that so? I'll have to look into that. Any links on this?
It is very "so". You can improve gas mileage and power output with a good tune, BUT only if you have the supporting hardware to allow for increased efficiency. Good EL headers (TWE is really the only option aside from some one-off fabrication), an intake and a tune could potentially get you +20 ft/lbs peak and maybe +10 hp at redline, but the biggest gains would be in area under the tq/curve especially under 4k rpm. My highway went up a very solid and repeatable 2mpg per tank.

without any bolt-ons a tune won't net you any milage increase, it's already pushed past the limit from the factory. A tune on a compltetly stock engine can improve driveability (most noticeable with manual transmission) and reduce/eliminate the knock that is present on even 93oct gas.

The hardware to get the described gains will cost ~$1000 plus labor and a good, thorough dyno tune is usually $200+

like everyone has said, extracting more power is possible but cost amounts of $ that most who buy a 2.5i are not willing to spend.

You could make 300+ hp n/a but it will cost something like $10,000 or you could make 200hp n/a and it could cost something like $1500

Also, ImprezaJohn, try not to get too caught up in the internet dick measuring contests that often erupt on here. lots of no so good info, but its easy to weed out with a little follow-up research.

Last edited by RaceFaceXC; 06-30-2010 at 06:50 PM.
RaceFaceXC is offline   Reply With Quote
Old 06-30-2010, 10:21 PM   #21
Back Road Runner
Scooby Guru
 
Member#: 60082
Join Date: Apr 2004
Chapter/Region: MWSOC
Location: Minnesota
Vehicle:
2004 Forester STI
Silver

Default

Quote:
Originally Posted by imprezajohn View Post
Ok, This is my first Subaru, I've spent many, many years in the American Muscle Car world and my understanding of these vehicles is pretty much zero. With that being said, what are, if any, the first N/A performance mods folks do to these vehicles? I drive 160 miles a day round trip to work, so reliability and gas mileage are an issue. Any help will be appreciated. Thanks.
Mileage comes in two parts:
  • Car weight
  • Aerodynamics

Stop and go traffic relies heavily on car weight for energy losses. Long distance driving is all about friction and the big factor of aerodynamics. Most modern engines are very good about completely burning the fuel that is run through the car. Mods can help put more air and fuel into the car and make more power, but efficiency doesn't really change. You just get to make more power. Some gains that you can do for efficiency is to pull in as cold of air as possible and to burn it as hot as you can without damaging parts, and you can up compression and change cams for more efficient operation.

For long distance, I would point you more towards improving aerodynamics and reducing friction. Every little bit helps. Run efficient tires and run them at high pressure. Run good synthetic oil and gear lube to keep machine friction low. Carefully select or remove trip pieces that improve aerodynamics (removing roof rack, installing smaller mirrors (some cars came with a couple options), adding a skid plate and some under tray bits to reduce under chassis drag, etc.).

For in town, find places you can remove some weight from the car. Run a lightweight batter, JDM, or race built bumper beams (very light), swap to aluminum suspension componments, pull the spare (maybe swap t runflats), swap on a CF hood and trunk. You can just run through the whole slew of parts and just try and drop weight. Even something like a lightweight flywheel drops 10 lbs. and reduces a a sizable amount of rotational energy used to accelerate the motor and car.
Back Road Runner is offline   Reply With Quote
Old 06-30-2010, 11:13 PM   #22
razrielle
Scooby Specialist
 
Member#: 205698
Join Date: Mar 2009
Chapter/Region: MWSOC
Location: Wichita, KS
Default

Quote:
Originally Posted by Cuddles View Post
Woa. I have the same exhaust, I think...but (no offense) yours sounds awkward. Maybe it's the camera. Check it:

YouTube- 09 Forester Magnaflow Cat Back (all positions)
yea I know, I have to mess around with it one day, its still kind of loose where it meets the headers, like, I have the spring bolts tightend down a good deal and its still loose, like, I cant tighten them down anymore, plus theres no resonator for the exhaust in there, I have to play around with it when I get time
razrielle is offline   Reply With Quote
Old 07-01-2010, 02:55 AM   #23
Audi20Tdriver
Scooby Newbie
 
Member#: 206040
Join Date: Mar 2009
Location: Carlsbad, CA
Vehicle:
2009 Audi A4 2.0T
APR Stage 1

Default

Quote:
Originally Posted by chazly413 View Post
It's not gonna be super lumpy. These aren't 9k rpm race cams.
dude you are seriously like a non stop contradiction. You are not adding anything of value to this thread going on about the OP getting new cams, headers and race exhaust for a car to do 160 mile per day commutes in.

Also, the thread you posted for me as proof are about the spicy cams matt put on his RS. Those are the more aggressive of the 2 cams from that company. There is the regular street and then the spicy.. Both are streetable; however, the spicy cams most definitely lead to a very lump idle. I have rode along in a RS with Spicy cams.. it was VERY noticeable as were the performance gains.. Still nothing like 12 PSI kicking in..

I considered doing cam work at one time and was leaning more toward the delta regrind then the spicy cams..
Audi20Tdriver is offline   Reply With Quote
Old 07-01-2010, 08:24 AM   #24
GEE-OTTO
Scooby Specialist
 
Member#: 201277
Join Date: Jan 2009
Chapter/Region: MAIC
Location: Arlington VA
Vehicle:
2009 Legacy GT
OBP

Default

Quote:
Originally Posted by Cuddles View Post
Woa. I have the same exhaust, I think...but (no offense) yours sounds awkward. Maybe it's the camera. Check it:

YouTube- 09 Forester Magnaflow Cat Back (all positions)
His has a lot of rasp in the note and yes the imprezas and foresters are the same in the CBE arena.
GEE-OTTO is offline   Reply With Quote
Old 07-01-2010, 08:27 AM   #25
GEE-OTTO
Scooby Specialist
 
Member#: 201277
Join Date: Jan 2009
Chapter/Region: MAIC
Location: Arlington VA
Vehicle:
2009 Legacy GT
OBP

Default

Quote:
Originally Posted by razrielle View Post
yea I know, I have to mess around with it one day, its still kind of loose where it meets the headers, like, I have the spring bolts tightend down a good deal and its still loose, like, I cant tighten them down anymore, plus theres no resonator for the exhaust in there, I have to play around with it when I get time

did you use the flat adapter plate that came with your CBE? I have a WRX CBE not on my car but I have one in the garage it wont mate flush b/c the stock connections uses a donut gasket you have to use that plate in place of donut and buy a gasket.
GEE-OTTO is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
A new car, new wife.........new member, new life?! 99ways2die Tri-State Area Forum 17 10-01-2005 08:24 PM
New Clutch..New engine...New Transmission! HeeroRaven Transmission (AT/MT) & Driveline 2 02-22-2005 10:00 AM
New wheels + new mods = new pics STi2001 Member's Car Gallery 9 05-26-2002 02:47 PM
New WRX, new member, new pics! jroot Newbies & FAQs 7 12-17-2001 11:24 AM
New snow... new cars....new i-club members... Fitz New England Impreza Club Forum -- NESIC 21 12-11-2001 11:15 AM


All times are GMT -4. The time now is 09:08 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.