How to increase more HP on a 2.5i. - Page 2

Garret 2010i · 05-19-2017, 10:58 AM

200whp on my 2.5i... yes lots of dollar bills spent

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GEE-OTTO · 05-19-2017, 12:17 PM

Are you running boost or is that just an extra mapped parameter ?

Garret 2010i · 05-19-2017, 12:33 PM

no boost no. its manifold relative pressure. vr dyno thinks its boost

rushtk · 05-19-2017, 12:50 PM

Ours is just a 02 impreza, rs2.5 sedan, manual. I don't expect it to be like my big subie (AWD RT Dodge Magnum) but would like to build it up for my son (his 1st car, 15.5 yrs old) so hopefully he stays subie and will be prepared for a wrx at graduation in 3 yrs.

AwdVt802 · 05-19-2017, 02:17 PM

Quote:

Originally Posted by banannersz

Hey fellas/ladies. i was wondering how to increase more horsepower on a 06 2.5i. without putting a turbo in it. more of like the easy basic things you can do to increase horse power. help me out

I had a 1998rs2.5 with borla headers, high flow cat, 2.5in cat back, injen intake, CM clutch, lightweight flywheel, strut bars front back, sway bars front back, lowering springs, short shifter. Car ripped with no tune. I never found a chip or tuned this car cus it was years ago but you prb get a chip or tune for an 06 easy now.

ssssssantimonio · 05-21-2017, 03:41 PM

Quote:

Originally Posted by Garret 2010i

200whp on my 2.5i... yes lots of dollar bills spent

Post your.mods.pls.

Garret 2010i · 05-21-2017, 08:08 PM

just buy one of everything, and dont stop till your broke! lol
im not really joking...

I boxed up the whole engine and shiped it to Tom at tech works.
his own 100mm 11.3:1 pistons, sti c rods and hardened crank
port and bended the heads to match his pistons, valve job and his stage 2 cams and springs
sti oil pump, fuel pump and injectors
act wrx clutch and light weight fly wheel, light weight pulleys
headers, low flow cat and 3" exhaust all the way
stock intake, i can't find one i like.
ecu flash for all my tuning

terrainasaurus · 05-22-2017, 01:00 AM

Quote:

Originally Posted by Garret 2010i

just buy one of everything, and dont stop till your broke! lol
im not really joking...

I boxed up the whole engine and shiped it to Tom at tech works.
his own 100mm 11.3:1 pistons, sti c rods and hardened crank
port and bended the heads to match his pistons, valve job and his stage 2 cams and springs
sti oil pump, fuel pump and injectors
act wrx clutch and light weight fly wheel, light weight pulleys
headers, low flow cat and 3" exhaust all the way
stock intake, i can't find one i like.
ecu flash for all my tuning

Uhmm, sound clip *PLEASE*

PA-Outback2000 · 05-22-2017, 02:33 PM

i assume this graph is an engine dyno, correct?

Garret 2010i · 05-22-2017, 02:50 PM

its wheel hp, if that's what you are asking

Patrick Olsen · 05-22-2017, 03:21 PM

Quote:

Originally Posted by PA-Outback2000

i assume this graph is an engine dyno, correct?

whp = wheel horsepower = chassis dyno

Preludicrous · 05-22-2017, 07:36 PM

Quote:

Originally Posted by AwdVt802

I had a 1998rs2.5 with borla headers, high flow cat, 2.5in cat back, injen intake, CM clutch, lightweight flywheel, strut bars front back, sway bars front back, lowering springs, short shifter. Car ripped with no tune. I never found a chip or tuned this car cus it was years ago but you prb get a chip or tune for an 06 easy now.

No chips but there are open source tunes out there. If only the AP's hadn't been discontinued for the 2.5i

Garret 2010i · 05-23-2017, 10:41 AM

id like to add a sound clip, but i can seem to

Patrick Olsen · 05-23-2017, 12:37 PM

Youtube?

PA-Outback2000 · 05-23-2017, 12:50 PM

Quote:

Originally Posted by Patrick Olsen

whp = wheel horsepower = chassis dyno

i just saw the "WHP" on the graph.

Garret 2010i · 05-23-2017, 08:55 PM

YouTube (Short URL)

see if that works, lol

terrainasaurus · 05-24-2017, 12:23 PM

Quote:

Originally Posted by Garret 2010i

https://youtu.be/fpTY7CSZJyg

see if that works, lol

I love the way that sounds, like it wants to go! Is that 2.5" piping?

Nice looking suba ^.^

Garret 2010i · 05-24-2017, 01:40 PM

no 3" all the way

PA-Outback2000 · 05-30-2017, 12:13 PM

Quote:

Originally Posted by Garret 2010i

no 3" all the way

Why did you do this?

terrainasaurus · 05-30-2017, 12:48 PM

Quote:

Originally Posted by Garret 2010i

no 3" all the way

Do you have wheel spacers? Or are the wheels offset so... they sit really nicely!

Garret 2010i · 05-30-2017, 08:24 PM

no wheel spacers, just an offset.

why not 3"? 2 1/2" would be too restrictive on my set up.

v2rocket_aka944 · 05-31-2017, 02:59 PM

Quote:

Originally Posted by Garret 2010i

no wheel spacers, just an offset.

why not 3"? 2 1/2" would be too restrictive on my set up.

3"...
must be the elusive "EJ60"

91 RS RA · 05-31-2017, 09:57 PM

2 1/2 inch is the biggest you want to go on N/A. This was the case for my EJ25 wagon and my Mondeo 2.5 V6.
With bigger piping you lose the 'Back pressure' in the system.
In other words the piping decreases the speed of flow of the exhaust and you end up losing the savaging properties of a well set up system.
3inch is fine for a turbo but not for N/A.
Don't know wh you would say 2.5 is too restrictive, I would say 3inch is too unrestricted.
But hey its you car and tune, if you like the 3inch then go for it. Would be interesting to see a back to back with a 2.5 and 3inch exhaust on the dyno
Does sound good for a N/A sub

williaty · 05-31-2017, 09:59 PM

Unless you're increasing airflow SIGNIFICANTLY (like putting $10k+ into the build in todays money), with the EJ25 non-turbo the biggest you want to go is 2.25". Anything more than that actually drops the exhaust velocity, hurts scavenging, and reduces power.

PA-Outback2000 · 06-01-2017, 09:29 AM

2.5" is max as we all know for N/A. not sure who told you to go that large.

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05-19-2017, 10:58 AM	#26
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	200whp on my 2.5i... yes lots of dollar bills spent * Registered users of the site do not see these ads.

05-19-2017, 12:17 PM	#27
GEE-OTTO Scooby Specialist Member#: 201277 Join Date: Jan 2009 Chapter/Region: MAIC Location: Arlington VA Vehicle: 2009 Legacy GT OBP	Are you running boost or is that just an extra mapped parameter ?

05-19-2017, 12:33 PM	#28
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	no boost no. its manifold relative pressure. vr dyno thinks its boost

05-19-2017, 12:50 PM	#29
rushtk Scooby Newbie Member#: 466374 Join Date: Apr 2017	Ours is just a 02 impreza, rs2.5 sedan, manual. I don't expect it to be like my big subie (AWD RT Dodge Magnum) but would like to build it up for my son (his 1st car, 15.5 yrs old) so hopefully he stays subie and will be prepared for a wrx at graduation in 3 yrs.

05-21-2017, 08:08 PM	#32
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	just buy one of everything, and dont stop till your broke! lol im not really joking... I boxed up the whole engine and shiped it to Tom at tech works. his own 100mm 11.3:1 pistons, sti c rods and hardened crank port and bended the heads to match his pistons, valve job and his stage 2 cams and springs sti oil pump, fuel pump and injectors act wrx clutch and light weight fly wheel, light weight pulleys headers, low flow cat and 3" exhaust all the way stock intake, i can't find one i like. ecu flash for all my tuning

05-22-2017, 02:33 PM	#34
PA-Outback2000 Scooby Specialist Member#: 161832 Join Date: Oct 2007 Chapter/Region: Tri-State Location: PA Vehicle: 2000 Outback Limited Black	i assume this graph is an engine dyno, correct?

05-22-2017, 02:50 PM	#35
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	its wheel hp, if that's what you are asking

05-23-2017, 10:41 AM	#38
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	id like to add a sound clip, but i can seem to

05-23-2017, 12:37 PM	#39
Patrick Olsen NASIOC Supporter Member#: 120 Join Date: Jul 1999 Chapter/Region: AKIC Location: Where the Navy sends me... Vehicle: 1997 Legacy 2.5GT 1996 Impreza coupe	Youtube?

05-24-2017, 01:40 PM	#43
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	no 3" all the way

05-30-2017, 08:24 PM	#46
Garret 2010i Scooby Newbie Member#: 355661 Join Date: May 2013 Chapter/Region: W. Canada Location: Winnipeg, MB Vehicle: 2010 Impreza 2.5i WR Blue	no wheel spacers, just an offset. why not 3"? 2 1/2" would be too restrictive on my set up.

05-31-2017, 09:57 PM	#48
91 RS RA Scooby Newbie Member#: 457410 Join Date: Oct 2016 Chapter/Region: International Location: Christchurch, New Zealand Vehicle: 1991 Legacy RS RA White	2 1/2 inch is the biggest you want to go on N/A. This was the case for my EJ25 wagon and my Mondeo 2.5 V6. With bigger piping you lose the 'Back pressure' in the system. In other words the piping decreases the speed of flow of the exhaust and you end up losing the savaging properties of a well set up system. 3inch is fine for a turbo but not for N/A. Don't know wh you would say 2.5 is too restrictive, I would say 3inch is too unrestricted. But hey its you car and tune, if you like the 3inch then go for it. Would be interesting to see a back to back with a 2.5 and 3inch exhaust on the dyno Does sound good for a N/A sub

05-31-2017, 09:59 PM	#49
williaty Scooby Guru Member#: 71092 Join Date: Sep 2004 Chapter/Region: MWSOC Location: Delaware County, Ohio Vehicle: 2005 2.5RS Wagon Regal Blue Pearl	Unless you're increasing airflow SIGNIFICANTLY (like putting $10k+ into the build in todays money), with the EJ25 non-turbo the biggest you want to go is 2.25". Anything more than that actually drops the exhaust velocity, hurts scavenging, and reduces power.

06-01-2017, 09:29 AM	#50
PA-Outback2000 Scooby Specialist Member#: 161832 Join Date: Oct 2007 Chapter/Region: Tri-State Location: PA Vehicle: 2000 Outback Limited Black	2.5" is max as we all know for N/A. not sure who told you to go that large.