Welcome to the North American Subaru Impreza Owners Club Wednesday October 1, 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 Archives > NASIOC Archives > General Forum Archive

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.
 
 
Thread Tools Display Modes
Old 08-21-2000, 06:10 PM   #1
jwooman
Scooby Newbie
 
Member#: 468
Join Date: Oct 1999
Location: Atlanta, GA, USA
Exclamation Swap engine or turbocharge it?

WRX engine and tranny = $6000 include labor
VS
Turbocharge the RS = $5000? include labor
Forget about the emission first....
Which one will you pick?
* Registered users of the site do not see these ads.
jwooman is offline  
Old 08-21-2000, 06:32 PM   #2
North Ursalia
Miss You Mom
Oct 1940 - Feb 2008

Super Moderator
 
Member#: 809
Join Date: Jan 2000
Chapter/Region: NESIC
Location: NH, Land Of Many Trees
Vehicle:
2000 2.5 RS, '14 For
92 5MT SVX

Post

I'd turbo the 2.5... WRX and STi engines are hard enough to get, plus you need wiring and ecu. When/if the transplanted engine breaks, how easy will it be to get another one, or even just get parts for it? I'm going to turbo the 2.5 (someday) because all the parts I'll ever need are at least in the US.
North Ursalia is offline  
Old 08-21-2000, 06:32 PM   #3
NickSTi
Scooby Specialist
 
Member#: 626
Join Date: Dec 1999
Location: Miami FL
Vehicle:
2001 Impreza 2.5 RS
Black Diamond Pearl

Thumbs up

Well look at it this way
A complete STi engine with ECU will run about 7k. BUT you can subtract your 2.5 which someone will surely buy from you. Total cost should be say 4k. not bad. Forget emissions and visual. Octane will be a problem.
A complete Turbo from Redline engineering + an upgraded ECU (not talking about Shiv's) will run you around 5k (yes 5k!). Forget emissions and visual. Just use premium gas.

Totally up to you, I prefer the latter.
NickSTi is offline  
Old 08-21-2000, 06:42 PM   #4
jwooman
Scooby Newbie
 
Member#: 468
Join Date: Oct 1999
Location: Atlanta, GA, USA
Post

hm...
How about I can get the engine, tranny, ECU and wiring harness within 5K? This will be my weekend "race" car. Octane fuel and WRX parts is not a problem to me....What would you think?
jwooman is offline  
Old 08-21-2000, 07:04 PM   #5
N/A
Scooby Specialist
 
Member#: 133
Join Date: Aug 1999
Location: Maryland (not by choice)
Vehicle:
2003 Echo-daily car
silver

Post

You could also just wait to see if somebody wrecks their new Impreza turbo and then use it as the donor. It would save you alot of time and trouble to do it that way. You could still sell your 2.5L engine and get some of the money back from the swap. It would be setup for the US octane from the factory and parts will be available for it. Hell you could still later on buy the 2.2L conversion for the EJ20.
Personally I am going to turbo the RS if I can't get ahold of a wrecked Impreza turbo. Others have turbo'd them and we know they will work. I just need to get a replacement to the stock MAF setup.
N/A is offline  
Old 08-21-2000, 07:36 PM   #6
NickSTi
Scooby Specialist
 
Member#: 626
Join Date: Dec 1999
Location: Miami FL
Vehicle:
2001 Impreza 2.5 RS
Black Diamond Pearl

Post

jwooman if this is a real STi engine (280PS) with low mileage then that is a great deal and I would go for it.
NickSTi is offline  
Old 08-21-2000, 08:11 PM   #7
codemunky
Scooby Guru
 
Member#: 1804
Join Date: Jul 2000
Chapter/Region: SCIC
Location: Irvine
Post

My friend has seen engine swaps on Imprezas. He says the process is ugly. You gotta almost strip the whole thing, wires, ecu, etc...
codemunky is offline  
Old 08-21-2000, 09:53 PM   #8
Ver.III
Scooby Specialist
 
Member#: 1185
Join Date: Mar 2000
Location: North of the border
Vehicle:
I flap my gums
and now I'm a specialist

Post

Pretty well all EJ20's from 97 and up with exception of the wagon I believe is 280ps.
I have done conversions and the most important part of the wiring I found is getting the harness with the engine(RHD) the rest is just tapping off power sources, grounds and gauges.
Ver.III is offline  
Old 08-21-2000, 10:57 PM   #9
Mikey
Scooby Newbie
 
Member#: 1647
Join Date: Jun 2000
Location: Toronto, Ontario, CAN.
Vehicle:
1999 Impreza 2.5RS
Silverthorne (SOLD)

Wink

Definitely go for the engine swap. There is no substitute for the real WRX engine...no 2.5 turbo kits can touch it. I know a guy who did the swap...awesome. Especially at that price, you won't be sorry.
Mikey is offline  
Old 08-21-2000, 11:20 PM   #10
shiv
Scooby Specialist
 
Member#: 607
Join Date: Dec 1999
Location: SF Bay Area, CA
Post

Mikey,
I would argue that a well set up EJ25 turbo will outperform an EJ20, both in power and in driveability. I suspect many EJ20 owner will eventually be upgrading to built EJ25s for "monster tune" engines. We'll see, I guess.

shiv
shiv is offline  
Old 08-22-2000, 07:07 AM   #11
Gambit
Scooby Specialist
 
Member#: 102
Join Date: Jul 1999
Location: The meeting place
Post

Keyword on shiv's post "well set up" that means lots of tuning with various piggyback computers or invest more on either a TEC-II or Link ECU. And more tuning.

I wish there's a meet b/t a similarly piced -time turbo 2.5 vs. a similarly priced-time WRX conversion.
Gambit is offline  
Old 08-22-2000, 07:21 AM   #12
jwooman
Scooby Newbie
 
Member#: 468
Join Date: Oct 1999
Location: Atlanta, GA, USA
Post

I am thinking the engine swap too. It has more potential to tune a WRX to 300+hp than a turbocharged RS without major modification. I think the WRX is more reliable as well, right?
jwooman is offline  
Old 08-22-2000, 08:17 AM   #13
JaiMak
Top Scoob 004
 
Member#: 697
Join Date: Dec 1999
Location: TSC headquarters
Vehicle:
1999 Top Scoob #4
Satin White Pearl

Post

Thing is, what shiv said is true- a properly built up EJ25 will make more power. There is no replacement for displacement. That's why the JUN built impreza uses a DOHC EJ25 that puts out 480hp.

When it comes to maximums, then yes, the built 2.5 motor will yield highest results.

However, when it comes to simplicity, that's a different story. Not everyone has the resources or knowhow to "properly" tune a built EJ25, but it's quite easy to simply toss in a wrx engine/transmission/electronics and forget about it. Especially soon when the turbo engines will be made available here. You could feasibly get them brand new, AND get replacement parts for the engine at the dealer. Then you could perform tweaks to that engine to get it up to par.

It should be a known fact, with higher compression pistons, and 460cc more displacement, you should be able to make significantly more power with an EJ25, which is what shiv is trying to say.

But does everyone need 350-400hp in their street car? No, and that is why many would just be happy with an EJ20 swap.

Personally, I'd tend to agree that maxium power would be acheived with an EJ25, but I'd rather go for the new EJ20s coming here.
JaiMak is offline  
Old 08-22-2000, 09:15 AM   #14
RotrPwr
Scooby Newbie
 
Member#: 1506
Join Date: May 2000
Location: Charlotte, NC
Vehicle:
1993 RX-7
Competition Yellow Mica

Talking

I think i would disagree with that statement. The 2.5 is a great platform. But faced with a motor swap vs. Turbo 2.5, i would take the EJ20, assuming its the STI motor. why? simple. Upgradeable. I think that for the average person,(someone who doesnt want to open the motor and start swapping pistons, rods, etc.) the EJ20 would be a much easier motor to coax more ponies from. Sure the 2.5 is very torquey, which makes driveability much better than the EJ20. But potential wise, i think the EJ20 Swap would produce higher HP levels and more reliablilty. And with possibly a larger turbo(which is feasable), intake, cat back(or axle back whichever), ECU, and some piggybacks, i believe the EJ20 could prob make somewhere around 380hp-400hp with some very very good tuning.
The 2.5 on the other hand, to acheive 380-400, you would have to dive into the motor. Swap in turbo pistons, higher strength rods, maybe thicker headgasket to reduce compression, larger fuel injectors, etc, etc.
By the time you get done with it, its almost not a 2.5 anymore I would go motor swap all the way.
but thats just me.

Darril
RotrPwr is offline  
Old 08-22-2000, 10:01 AM   #15
adam99rs
Scooby Specialist
 
Member#: 20
Join Date: Jun 1999
Location: New York
Post

darril - thanks for pointing out the obvious....many people here forget about the inherent weaknesses in the EJ25.

jeff, I am doing the swap in my own car...STi V5 motor, ecu, etc. sure, it costs more than I spent on my turbo EJ25, but I was able to sell that kit, thus reducing my outlay.

In the end, I expect many more tuned EJ20's than built up EJ25's, if for nothing else than for the ready-made aftermarket. The EJ20 is light years ahead in terms of product availability, that the EJ25 crew has catching up to do. others here (like me) are pursists...I wanted an STi V5 from the factory, tried to get one (in vain), and was unable to import it for everyday use. so, being of the midset that the 2.0 liter belongs in teh car, that's what I am going with. I can't wait to see built up EJ25's though, as modding across te engine and model range all improves the breed.
adam99rs is offline  
Old 08-22-2000, 10:08 AM   #16
f1seb
Scooby Newbie
 
Member#: 1935
Join Date: Jul 2000
Location: Long Island
Post

hey I posted the same thing last week....well almost......same response though a divided group on turboing the 2.5 Rs or swapping the engine.....im still trying to figure out how im going to approach the build up part of the RS.
f1seb is offline  
Old 08-22-2000, 10:32 AM   #17
shiv
Scooby Specialist
 
Member#: 607
Join Date: Dec 1999
Location: SF Bay Area, CA
Post

It's a stretch to see a stock EJ20 making much more than 320hp. While a few have supposedly made as much as 350hp, the haven't exhibited the most stellar reliability records. Turbocharged EJ25s at 7-8psi, on the other hand, start out at 270-280hp. Throw in some good management, a few more pounds of boost and a good exhaust, and they pump out over 320hp without sweating too much. And with equal, if not better reliability, I would argue. Certainly better in terms of driveability.

shiv
shiv is offline  
Old 08-22-2000, 01:01 PM   #18
RotrPwr
Scooby Newbie
 
Member#: 1506
Join Date: May 2000
Location: Charlotte, NC
Vehicle:
1993 RX-7
Competition Yellow Mica

Have a Nice Day?

Shiv,
i really cant forsee any 2.5 pushing 270-280hp by just bolting on a turbo kit@ 7-8psi. According to your post, your saying that a bolt on turbo will produce 270-280hp before engine management piggybacks? I dont buy that. Look at just about every other turbo kit released for most other NA to Turbo conversions. Typically all Greddy,HKS,Hahn RC, etc turbo kits see a 50-65 hp increase, intercooled, with the exception of DRAG which seems to get anywhere from 100-125hp from their kits, but they usually include larger injectors. Oh and that Dealer Alternative kit for the miata, but that runs 12psi, which is rather much for a NA to Turbo conversion. Now start adding fuel, and AR controllers and you can coax maybe another 25-35hp out of the engine, but i would say no more. So what makes the Minnam or JC kits special? I'm not trying to be a know-it-all, but i'm an honest man, and i see honest numbers alot. I would have to see the proof in the pudding
270-280hp is a 105-115hp increase over stock when i think Minnam is claiming a 50-60hp over stock. What gives?

Darril
RotrPwr is offline  
Old 08-22-2000, 01:26 PM   #19
Gambit
Scooby Specialist
 
Member#: 102
Join Date: Jul 1999
Location: The meeting place
Post

It's prolly in Shiv's super Impreza 2.5RS heh!
Seriously, you really need alot of engine management controls to get that 2.5l turbo to run smoothly. Last i checked that,minnam stage II gives out about 60-80hp...so that's like 220hp-240hp to start. I think the boost is at 7psi. That's when it only needs an AFC and and ITC. once you up the boost.... I dunno, you will need this and that nick nacks to keep the entire package happy.
Gambit is offline  
Old 08-22-2000, 01:47 PM   #20
calmliquid
Scooby Newbie
 
Member#: 2058
Join Date: Aug 2000
Location: Glenolden Pa U.S.A.
Post

You can run up to 9psi of boost and not need any elctronics just a rising rate pres. reg. I know this from talking with Rallispec (I am getting ready to buy a turbo and am shopping around)or at least that is what thay have told me (and I believe them)as for the base h/p you would get??? I don't claim to know just repting what I was said to me.
calmliquid is offline  
Old 08-22-2000, 02:08 PM   #21
adam99rs
Scooby Specialist
 
Member#: 20
Join Date: Jun 1999
Location: New York
Post

Rotrypower - Shiv's number are accurate...I ran 18, yes 18 psi on my stock block, stock head, stock injector RS, and at those levels, I figured it was making a good 320 hp, based on my ET of 12.68, and trap of 108 and change in the 1/4 mile.

I still disagree with Shiv, since we are comparing apples to oranges in terms of dyno results. Some of the charts for STi V5's dynoed as high as 300 hp at the wheels, without mods. we can't compare shiv's dyno results to the UK guys, as they were not on the same dyno's. I still think th EJ25 is a great platform, and i'm pleased as hell my ran as well a it did for as long as it did (40k plus miles), but to me, the 2.0 belongs in the car, and with the 2.5 being eliminated from the subaru lineup, the EJ20 still represents the direction the aftermarket will concentrate on for obvious reasons. Having driven a stock STi v5 in Japan, I can attest to minimal lag, great driveability, and great redline (which I happen to like). Now add in an upgraded turbo, cams, 3 inch downpipe, and turn up the boost, and I I know these motors have 400 in them.. Shiv, you must remember that not too many of the Uk guys are running anything but stock turbos.....yet they are still making good power. We will argue about this till we all drop dead!
adam99rs is offline  
Old 08-22-2000, 02:13 PM   #22
shiv
Scooby Specialist
 
Member#: 607
Join Date: Dec 1999
Location: SF Bay Area, CA
Post

Rotrpwr, all the other cars you mentioned have 1.6 to 1.8 liter engines. A big 2.5 liter will see more hp increases. Take a look at specific output and you'll see that it's in line with other NA to Turbo conversions. Besides, on the UPRD dyno, my once stock Minnam Stage II at a poorly tuned 7.5psi dyno'd at 183 wheel hp, just 7hp less than a Lancer EVO VI.5 Mak Edition on that same dyno (which, BTW, is known to make more power than the Sti v.5). No imagine that same motor with more boost and real tuning. No question in my mind that this is the motor to have for big hp numbers and good driveability.

shiv

[This message has been edited by shiv (edited August 22, 2000).]
shiv is offline  
Old 08-22-2000, 03:12 PM   #23
samurai
Scooby Newbie
 
Member#: 696
Join Date: Dec 1999
Location: Union City, CA USA
Vehicle:
2005 WRX STi
Aspen White

Post

Cusco has an Impreza with a 2.5l turboed engine running in the ANTCC. But, they changed the piston heads, piston rods, etc.

Turbo charging is cool. Just make sure that the boost you put into the engine can handle it. The 2.0l swap is great. The engine here is built to run at higher chamber pressures, higher heat and higher RPMs. Its just that it sorta costs more in the long run (IMHO) since you need Super Unleaded + Octane Boost to have it run properly.

Tim
samurai is offline  
Old 08-22-2000, 04:44 PM   #24
Ver.III
Scooby Specialist
 
Member#: 1185
Join Date: Mar 2000
Location: North of the border
Vehicle:
I flap my gums
and now I'm a specialist

Post

Adam,
I glad someone else can see the same views as me......!!!
this debate will never end but I guess when the new Impreza's come out, we will see where the aftermarket swings....
Ver.III is offline  
Old 08-22-2000, 05:12 PM   #25
shiv
Scooby Specialist
 
Member#: 607
Join Date: Dec 1999
Location: SF Bay Area, CA
Post

The aftermarket swings towards where the money is. Not necessarily towards performance.

shiv
shiv is offline  
 

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 On
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Valve Job -Pull the engine or leave it in? Mat L Normally Aspirated Powertrain 7 03-13-2010 10:46 AM
Places in or around la county that swaps engines? Juztjin Subaru Conversions 4 08-23-2005 09:03 PM
Should I swap my 2.0L sohc engine?..or do it up?.. Arnie_Legacy Normally Aspirated Powertrain 7 07-04-2005 07:04 PM
Porsche engine swap - SVX or WRX? soloracer Subaru Conversions 73 05-06-2004 05:42 PM
What woud you do? Swap it or part it? DubRxGrl84 General Community 21 01-30-2004 01:30 PM


All times are GMT -4. The time now is 11:17 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.