Welcome to the North American Subaru Impreza Owners Club Friday July 25, 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 with bolt-on Forced Induction 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 10-11-2001, 12:21 PM   #1
MINDGAME
Scooby Newbie
 
Member#: 7500
Join Date: Jun 2001
Location: Southern California
Vehicle:
2002 2.5 TS Wagon
No, it's not a WRX...

Default Engine Internals

Do you think it would by wise to upgrade the internals of my 2.5 before bolting on a turbo?

Pistons seem to be the most popular victim of turbos (well maybe tranny actually), so getting higher quality pistons as well as lowering the compression seems like a start. What else can be/should be done to make a NA engine accomodate a turbo like the ej22t or ej20t? Crank? Rods? Cam?

(FYI- I will be purchasing my turbo from Shiv if he decides to continue with the packages after his first run.)

Thanks.
* Registered users of the site do not see these ads.
MINDGAME is offline   Reply With Quote
Old 10-11-2001, 01:05 PM   #2
HndaTch627
Scooby Guru
 
Member#: 6551
Join Date: May 2001
Chapter/Region: MWSOC
Location: Carol Stream, IL
Vehicle:
'01 GC8 Dinged STM
'09 Concours 14 ABS Black

Default

the pistons normally hold up until you run lean to the point you get detonation and cast pistons don't take kindly to detonation. I would go witha set of forged pistons but be prepared for them to be a little on the noisy side when they are cold. The rods should hold if you are planning then pushing no more then 9 PSI daily driven.

Jeremy
HndaTch627 is offline   Reply With Quote
Old 10-11-2001, 09:11 PM   #3
jeff22
Scooby Newbie
 
Member#: 7534
Join Date: Jun 2001
Location: manchester, NH
Vehicle:
99 impreza rs-t
rally blue pearl

Lightbulb

what do you want to do? If you want a bullet proof high horsepower bottom end, forged pistons are a must! connecting rods are a good insurance. you went that far, get the crank knife edged and everything balanced! call cobb tuning they will help! Don't call B-spec!
jeff22 is offline   Reply With Quote
Old 10-11-2001, 09:34 PM   #4
kaos200
Scooby Guru
 
Member#: 2692
Join Date: Oct 2000
Chapter/Region: SCIC
Location: SoCal
Default

Quote:
Originally posted by jeff22
what do you want to do? If you want a bullet proof high horsepower bottom end, forged pistons are a must! connecting rods are a good insurance. you went that far, get the crank knife edged and everything balanced! call cobb tuning they will help! Don't call B-spec!
MINDGAME...HndaTch627 is right, forged pistons are not the quitest of pistons!
However, I suggest them as a safety measure, headwork always is NICE! Springs definitely.
But most importantly, is the Fuel system, and engine management that support the entire system. THOSE my friend are the key. They have been discussed enough in this forum that I believe I can say a search will suffice.
You can also get rods, or you can buy 2.5 rods to shotpeen and use ARP bolts on. BTW I have a set for sale so you can do it to those while you drive your car

Last edited by kaos200; 12-06-2001 at 12:51 AM.
kaos200 is offline   Reply With Quote
Old 10-12-2001, 12:03 PM   #5
MINDGAME
Scooby Newbie
 
Member#: 7500
Join Date: Jun 2001
Location: Southern California
Vehicle:
2002 2.5 TS Wagon
No, it's not a WRX...

Default

Sorry to sound ignorant, but what kind of noise do forged pistons make? Do they just make the ambient noise of the engine louder, or is there some sort of specific noise associated with them?

The noise that a set of stiff-ass coilovers makes bothers me, but the noise from a loud aftermarket exhaust is music to my ears...
MINDGAME is offline   Reply With Quote
Old 10-12-2001, 01:01 PM   #6
efoo
Scooby Specialist
 
Member#: 80
Join Date: Jul 1999
Default

ever hear an old Volkswagon beetle with a diesel engine?

that's very much like forged pistons.

clank-clank-clank-clank-clank-clankity-clankity-clankity-clank-clank-clank-clank-clank-clank..

all day long too. I've been around Imprezas with forged pistons in EJ25s. The noise didn't really subside even after a good hour of driving. I don't think the pistons were the wrong size or anything either - just loose by nature.

I sure wouldn't want forged pistons in my daily driver. It doesn't sound nice at all -- not like a deep exhaust.
efoo is offline   Reply With Quote
Old 10-12-2001, 01:11 PM   #7
MattC
Scooby Specialist
 
Member#: 158
Join Date: Aug 1999
Chapter/Region: NESIC
Location: CT
Vehicle:
2011 STi
PBP 1999 2.5RS RBP

Default

I have heard EJ25 motors with forged pistons too, most of the time with Efoo present They sound, just like Efoo said, like diesel motors. Proper tuning is all you need. I really don't want to open my engine, and am dreading the time when I'll have too.

Cheers,

MattC
MattC is offline   Reply With Quote
Old 10-12-2001, 05:51 PM   #8
MINDGAME
Scooby Newbie
 
Member#: 7500
Join Date: Jun 2001
Location: Southern California
Vehicle:
2002 2.5 TS Wagon
No, it's not a WRX...

Default

So if I really want to do a turbo engine right, should i just buy a ej22 short block and build up from there? I mean that engine is made to turbo right...so I should be able to run a higher boost with this foundation. Obviously this route will be a lot more expensive than just modifying my 2.5, but I want considering this car to be a project car.
MINDGAME is offline   Reply With Quote
Old 10-12-2001, 06:12 PM   #9
kaos200
Scooby Guru
 
Member#: 2692
Join Date: Oct 2000
Chapter/Region: SCIC
Location: SoCal
Default

Quote:
Originally posted by MINDGAME
So if I really want to do a turbo engine right, should i just buy a ej22 short block and build up from there? I mean that engine is made to turbo right...so I should be able to run a higher boost with this foundation. Obviously this route will be a lot more expensive than just modifying my 2.5, but I want considering this car to be a project car.
the EJ22T is the one that came turbo'd. There are differences between the two. However, If you are going to run more than 10psi, from a nicely sized turbo. ATLEAST install pistons in that motor, if not pistons and hardened/upgraded rods.
kaos200 is offline   Reply With Quote
Old 10-13-2001, 02:41 PM   #10
5252
Guest
 
Member#:
Default

Got my bill for my Pauter rods and my JE forged pistons and total seal rings. Ouch mommie. I would have to say no, don't get internals.
  Reply With Quote
Old 10-13-2001, 03:13 PM   #11
DJIMPREZA
Scooby Specialist
 
Member#: 1199
Join Date: Apr 2000
Location: Caracas, Venezuela
Vehicle:
1994 Supra+1K, 22b
alike, 07STI

Default

I have 92.5 mm BPM forged pistons and they don`t sound like you say, they are just like the OEM ones about it`s sound... soemtimes a little clank for 1 minutes when during cold starts
DJIMPREZA is offline   Reply With Quote
Old 10-14-2001, 04:38 AM   #12
HndaTch627
Scooby Guru
 
Member#: 6551
Join Date: May 2001
Chapter/Region: MWSOC
Location: Carol Stream, IL
Vehicle:
'01 GC8 Dinged STM
'09 Concours 14 ABS Black

Default

I disagree with the noise they supposedly make, but they do knock at cold start.

jeremy
HndaTch627 is offline   Reply With Quote
Old 10-14-2001, 12:40 PM   #13
kaos200
Scooby Guru
 
Member#: 2692
Join Date: Oct 2000
Chapter/Region: SCIC
Location: SoCal
Default

Quote:
Originally posted by HndaTch627
I disagree with the noise they supposedly make, but they do knock at cold start.

jeremy
well, all I know is... They DO make noise... atleast all the J&E and Weisco etc that Ive heard/ heard of.
kaos200 is offline   Reply With Quote
Old 10-15-2001, 01:04 AM   #14
milkman
Scooby Specialist
 
Member#: 8066
Join Date: Jul 2001
Chapter/Region: MWSOC
Location: Indiana,
Vehicle:
Y2K RSt
Sedona Mars Red Pearl

Default

I don't see why properly sized and fitted pistons would make any more noise then stock, maybe someone could tell me why, but this is something I've never heard of, and yes I've put pistons in a 351W before. If you want to build 300WHP + eng then build the block. I'm in the camp of why do it until you need to my self.
milkman is offline   Reply With Quote
Old 10-15-2001, 04:17 AM   #15
HndaTch627
Scooby Guru
 
Member#: 6551
Join Date: May 2001
Chapter/Region: MWSOC
Location: Carol Stream, IL
Vehicle:
'01 GC8 Dinged STM
'09 Concours 14 ABS Black

Default

kaos i wasn't disagreeing with you it was the guy making it sound like a rod is tapping the block, yes JE's are rather noisy but well designed pistons. Any quality material piston will be louder.

Jeremy
HndaTch627 is offline   Reply With Quote
Old 10-15-2001, 08:55 AM   #16
outback motorsports
Scooby Newbie
 
Member#: 4084
Join Date: Feb 2001
Location: buena park, ca.
Default rods and pistons

we have our own h-beam rods, arp 2000 bolts, lighter than pauters for $500 i-club price. we also stock 6 diff.2.5 piston configs for turbo usage.we stock bearings too see ya steve 714 994 5222
outback motorsports 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
Is it worth upgrading engine internals? wrx182 Factory 2.0L Turbo Powertrain 14 12-20-2001 02:50 PM
Who's good with engine internals? WRXwannbe Bay Area Impreza Club Forum -- BAIC 0 10-23-2001 03:28 AM
Engine internals bigbuyer2477 Factory 2.0L Turbo Powertrain 22 05-24-2001 06:55 PM
engine internals for legacys !? sub soob Legacy Forum 5 04-04-2001 12:35 AM
Automotive engineering international - info on new flat 6 Steve00RS General Forum Archive 0 10-17-2000 07:35 AM


All times are GMT -4. The time now is 07:56 AM.


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.