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Old 08-29-2005, 09:59 PM   #1
dntouch
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Default This is it i'm diving in.2.5 build...

Allright i have driven a 1990 VW Corrado for the last 8-9 years. I have literally 20,K+ into the car and its become strictly a track car. Its awsome at the track and autocrosses but the road isnt even an option.

I intend to build my 2004 OBS into a streetable (back and forth to work)naturally aspirated machine i can take to the track when i want.. (and not trailer it)


Also i intend to dump (yes dump) around 6500.00 into the car.

I am allmost definetly going with the Praxis system for the car. Seems like the best of all worlds except the additional wieght (30lbs).

I will need wheels and tires but that shouldnt be included into the price(kinda a standard issue item for me)

I am eying up the COBB stage 3 kit. I have 26,000 on the car so i intend to call up the dealer and cancel my extended service plan. (for obvious reasons) Warranty after i start this build is no longer an issue.

I am relatively new to the Subaru scene and really need some heartfelt words of wisdom.

Please remember that its going 20miles to work and back a day. I realize i am going to lose MPG but hopefully it wont account for more that 5 MPG if driven in a mature manner.


Guys (gals?) give me some strong advise. I like what COBB has to offer but without 1st hand knowledge of their stuff (besides my crank pulley) I need to know i'm buying something that will hold together and more importantly "PERFORM"..
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Old 08-29-2005, 10:04 PM   #2
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v7 swap. stay out of boost for daily driving.
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Old 08-29-2005, 10:09 PM   #3
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PLEASE READ THE ABOVE POST>> Naturally Asiparated... Thanks..


I have had a supercharged car long enough to know that if its there i will use it.. I am not looking for 300HP i am looking for a car that even my wife could jump into at times and still drive.. (allthough i'm sure the exhaust wont go over good)

Thanks for the responce. I thought about it but i'm living life a little more tame at the moment.

If i didnt own the Corrado I would be driving an STI allready. Seems i have a bug that wont let me leave anything stock, and the STI would have cost me a fortune.
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Old 08-29-2005, 10:09 PM   #4
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if you're really serious about dumping that kind of money in, you should talk to twe directly
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Old 08-29-2005, 10:10 PM   #5
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^ what that dude said. spend ur money smart, a STI powered OBS would be pretty saweet, especially if its a sleeper exterior.
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Old 08-29-2005, 10:11 PM   #6
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OK .. Can you tell me Why TWE and Why not COBB? Or someone else.?

Please dont take my posts as biased towards COBB i am looking into the "if someone else then why ?"
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Old 08-29-2005, 10:12 PM   #7
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Quote:
Originally Posted by dntouch
PLEASE READ THE ABOVE POST>> Naturally Asiparated... Thanks..


I have had a supercharged car long enough to know that if its there i will use it.. I am not looking for 300HP i am looking for a car that even my wife could jump into at times and still drive.. (allthough i'm sure the exhaust wont go over good)

Thanks for the responce. I thought about it but i'm living life a little more tame at the moment.

If i didnt own the Corrado I would be driving an STI allready. Seems i have a bug that wont let me leave anything stock, and the STI would have cost me a fortune.

uh oh i made someone mad. if you MUST have your precious ej25 then fine. just saying it would be cheaper if you swapped it, more reliable and could probably get more power out of it too.
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Old 08-29-2005, 10:13 PM   #8
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Quote:
Originally Posted by Dash_Martino
^ what that dude said. spend ur money smart, a STI powered OBS would be pretty saweet, especially if its a sleeper exterior.

I have had that thought for a couple of weeks. But honestly i dont want my car down for 2+ weeks while i do an engine swap. Plus i havent a clue where to start with something like that.. (in Subaru's at least)
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Old 08-29-2005, 10:15 PM   #9
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Quote:
Originally Posted by svek
uh oh i made someone mad. if you MUST have your precious ej25 then fine. just saying it would be cheaper if you swapped it, more reliable and could probably get more power out of it too.

No ones mad... I'm just trying to do a NA build.. And streetable.

Also as far as price goes what you are saying is that the engine will yield more power (a lot more) and so what about the drivetrain. There is no way the rest of the car would hold up.
I do plan on a limited slip and engine mounts and such but the trans and center diff would be gone on the first launch. (thats my guess anyway)


I think i would be looking at a ton of $ to do it properly and make it last.
I can tell this posting might not get me anywhere fast..
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Old 08-29-2005, 10:29 PM   #10
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Hey man. I just finshed my motor. I built a N/A 2.5. Seriously, save your money on the build. Take the heads to a reputable engine builder and have them flow and port the heads, get a set of cams (TWE makes some awesome stuff), get headers, port the intake manifold, etc. Don't go nuts with a buildup b/c you're not going to get the performance you're probably expecting. I am being held up by a bad slave cylinder but I'll let you know how mine turned out.

*Side Note* I started with intentions of doing a high compression N/A motor. I worked at a very reputable engine shop that does almost all race stuff. I balanced and blueprinted the bottom end, ported the heads, did cams and some other stuff. I realized very quickly that if I want to make serious power, I'm going to have to go turbo. If you're looking for a better than stock daily driver, then take my suggestion before you spend all that money. Take the rest and invest in suspension.
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Old 08-29-2005, 10:36 PM   #11
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Yeah the suspension is going to be Praxis..

As for the heads. I had thought to bring them to a local guy that did mine on the VW very reputable guy and shop. I'm not looking for a screamer ( i knew that wasnt going to happen N/A.) but in combination with suspension and knowledge of driving i thought the car could be fun at the track also.

TWE is brought up again .. Does someone have a link to their site, or do they strictly sell to various tuners.


Do you have a recomendation on compression and what type of cam and valves are we talking about. Or did you just do a 3 angle job on the stock valve.?

Keep it coming
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Old 08-30-2005, 12:51 AM   #12
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http://www.techworkseng.com/Products...ngine_Cams.htm

there is a link to twe. TWE is favored around here over cobb. They have a lot of expensive goodies.

For 6 grande you could prolly get a new shortblock or high compression pistons to boost the compression up to 11:1 and push over 200 hp NA.

Here is cobbs website:http://cobbtuning.com/impreza/
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Old 08-30-2005, 01:17 AM   #13
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I dont like the sound of this.

You cant modify the EJ25 THAT much while staying N/A and STILL keep the car daily drivable... All the hard core EJ25 internal work that has been done on cars here usually end up in the shop more than driving around...

If you want it to stay streetable, stick with bolt on mods and maybe cams and dont expect much (skip aftermarket clutch/flywheels too)

If you want my advice, skip this and go for a better engine that will be 100% daily drivable, and skip the Praxis as well its a waste of money.
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Old 08-30-2005, 01:56 AM   #14
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Quote:
Originally Posted by Kostamojen
You cant modify the EJ25 THAT much while staying N/A and STILL keep the car daily drivable... All the hard core EJ25 internal work that has been done on cars here usually end up in the shop more than driving around...

If you want it to stay streetable, stick with bolt on mods and maybe cams and dont expect much (skip aftermarket clutch/flywheels too)

If you want my advice, skip this and go for a better engine that will be 100% daily drivable, and skip the Praxis as well its a waste of money.
I couldn't agree more.

You can't have a streetable, high-power N/A EJ25 that will make big numbers and last a long time between rebuilds-- not without a huge chunk of cash. The Praxis suspension setup is prohibitively expensive for what it provides, reducing the cash you have on hand to properly achieve your goal of a reliable, high-power N/A EJ25. Ditch the Praxis in favor of a more conservative approach such as upgraded springs, struts, and swaybars, and dump the additional funds into a full bottom end build-up with TWE's products.

If you're looking for the high-power N/A holy grail, do some searches in this forum and learn all you can before you decide on a plan of action. There are plenty of veterans who chased this dream only to find a nightmare of broken engines, rebuilds, and an endless money pit. I hope the same doesn't happen to you.

-Mark, broke college student who long ago gave up his aspirations of N/A supremacy
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Old 08-30-2005, 02:30 AM   #15
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Don't go with praxis. Some magazine went with Praxis as their suspension on an STi and well they changed it to HKS coilovers after a few months (too expensive to maintain). Stick with regular coilovers built for weekend track racing/comfortable daily driving.

If you want some minor N/A build up mods. I'd say Intake, exhaust, header, cams, Rallitek chip, pulleys, and maybe even clutch/flywheel if you n your wife feel like workin out while you drive. As far as brands go... TWE headers more power corny sound, Perrin pulleys, Injen or Cobb intake, Cobb or custom catback, exedy clutch/flywheel the 500 dollar cheap one that can hold somewhere around 300 ft. lb., and for cams TWE or COBB i'd jump on TWE's though.

That should put you around 200-220hp range enough to keep up with a stock WRX probably, and most likely a blast at the track too.

EDIT: oh yea if you're wife wont like the car to be loud get some kind of Resonator that'll tone the sound down a lil bit.
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Old 08-30-2005, 06:27 AM   #16
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OK guys thanks..

I see some good points coming my way.. I appreciate it.. I didnt know the bottom end wasso prone to "not holding together" but i guess when you start throwing higher compresion into the mix anything can break..

Gotta work right now i will jump into this a little later today.



I appreciate the help..
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Old 08-30-2005, 06:49 AM   #17
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Is anyone reading this guys post??? All I see are a bunch of post that are telling the guy not to buld up a high power N/A ej25. Do any of you know what cobb stage 3 consists of? IMO I don't see any problems at all with trying to build an ej25 up to this level. All it is is full bolt on mods, with cams and heads. There is no reason that it will not be totaly streetable. I don't see anything in his post that mentions high compression ratios, or anything that would compromise his car. Yeah your car may run a littlte rougher and be a little louder, but I think it will be very relaible. There are a lot of guys running around out there with these kinds of mods. A lot more than you think.

You will also want to spend some money on tuning for the car. You entered the market at the right time. You have the choice between running the perfect power SMT-6, or getting your ecu reflashed by I-speed. I've heard nothing but great things about the perfect power, and assume great things are to come with the I-speed reflah. I'm going to say that tunning is going to be a must if you want to get all of the power your mods will make, and to make the car more much more reliable.

Good luck with the build, and don't listen to all the people who tell you you're crazy and you should just spend the money on a swap. If I reacall I don't ever reading that you want 250whp. I'm assuming that you will be more than happy with about 150-160awhp.
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Old 08-30-2005, 11:45 AM   #18
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I am not going to get involved in all of the pissing and other BS that is contained in this thread. Read my thread if you are serious about making some power.
http://forums.nasioc.com/forums/show...highlight=dyno

It is a very simple formula:
Cobb Stage II coupled with Spicy Cams
Cometic .027" thin HG for 11.5:1 CR
Exedy lightweight flywheel
STOCK ECU

That is all. Save you pennies. Skip the headwork. Don't pay a cent for fancy forged pistons. My car makes equal power to a stock WRX. It is streetable. It passed emissions easily. I've still got 10-15hp on the table from not having aftermarket EM to tune it with. It is pig rich up top.

The gains from headwork will be around 10-15hp, if you want to go that route. That's the point that it gets a bit less streetable, and fuel mileage will drop into the teens. I get 23mpg around town when I behave myself. Open hwy is more like 25mpg.

I still have never seen a dyno for the comparible TWE package. TWE has a bunch of groupies largely because they deliver product a lot quicker than Cobb. TWE's customer service is phenominal. Somehow that has made people believe they have the best product. Don't get me wrong. They make great products. But noone on this board has ever proven to me that it is a better product than Cobb's!!!
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Old 08-30-2005, 01:37 PM   #19
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I'd say if you're doing a NA build up look at what Matt has done. I think this is a great balance of power and reliability. With Cams you'll be totally streetable. And like he said once you get into high compression pistons thats where stuff can get a little crazy. But with the right tuning I think you can still get a very driveable car. It's all about the tuning IMO. Same with Turbo same with NA builds.

I'm not going to say that TWE is better than Cobb. Matt has a good point. I'm prolly going to go with TWE. Not because people say so. Because I've done some research and I like what TWE has to offer. I think they have a clean product. And their products match my needs slightly more than Cobb's. I will still be using a Cobb cold air intake. It's the best. For cams look anywhere. You can get them a lot cheaper thru smaller less known companies for 1/4 of the cost. And for tuning I'm really digging the RS reflash thru I-Speed.

cheers

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Old 08-30-2005, 11:37 PM   #20
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Yes finally a couple people that see what i want. Drivable and still fun to drive.

I am going to contact COBB just to feel them out and see what they want to sell me. I will also talk with TWE.

Should i guess that the cams arent that big of a deal.? (installation) It wouldnt be the first time for me but on a Subaru "YES".

I did notice that someone mentioned the stage2 package from cobb. Why not do the head.? Just curious. I have read that the stock setup on the 2.5 is a pretty good flowing head but will there be a great deal of improvement over stock with an aftermarket head or my own sent to a shop to get ported.?

Also has anyone disproven how well the plastic intake runners flow.? I am coming from an all metal car,, this plastic stuff under the hood really makes me wonder and is there any options for aftermarket throttle-bodies.?

All for now..
I need to nail a plan down by this coming Monday.. As tuesday will see alot of orders being made.
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Old 08-31-2005, 12:42 AM   #21
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Well call around. See what you get from the deals. Keep in mind they're in the business to sell stuff. Please don't take this the wrong way, BUT.... If you're asking these questions I don't think you're ready to be dumping a lot of cash into this project unless you just have to much money that you don't know what to do with it. Given that....

The general concensus is that cams are a great up grade and prolly worth the 500 for the parts and you can kind of justify the 600 dollar installation. But the heads and cams are going to be about 3k. Just to let you know and you're now for sure pulling the engine out so maybe stack a few hundo more onto the install. If you've never done this with an RS you might want some friends that have seen this done or do a lot of reading.

There was a lot of talk about the plastic manifold but then subaru ditched the idea in the 05 models so people kind of got to think that maybe they did that for a reason. You can extrude hone the metal manifold but you're really not going to be like wow that's a big difference. It's one of the last things you should look to do.

I'd say do some more reading man. If you don't know who dan coty is you're prolly not ready to drop 7k on a high output ej25. Just don't want to see you end up dumping all that cash on parts then spend that much over again to get it running reliably. Don't get discouraged. It's a big job. Good luck.

cheers

garrett
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Old 08-31-2005, 03:12 AM   #22
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It'll cost you about half of that to get over 200 crank HP. You don't need to bump compression either to get there. Bolt ons should get you there with some cams.

cheers

garrett


Quote:
Originally Posted by rsracer2005
http://www.techworkseng.com/Products...ngine_Cams.htm

there is a link to twe. TWE is favored around here over cobb. They have a lot of expensive goodies.

For 6 grande you could prolly get a new shortblock or high compression pistons to boost the compression up to 11:1 and push over 200 hp NA.

Here is cobbs website:http://cobbtuning.com/impreza/
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Old 08-31-2005, 07:59 AM   #23
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I think you're being a bit too ambitious going with the headwork right off the bat. The 2.5L engine has a lot of capability before worrying about the heads. Take a look at what just a well prepped street-prepared 2.5RS (GC6) is acheiving without touching the heads at all.

Head over to Boxer4racing.com and click on Project Cars, then select the RS. Notice all the FTDs. Yes, Rankins is an excellent driver, and those FTDs are rarely up against a car in a Prepared class, but everyone that's driven the car says it's insanely easy to drive very fast in. Check out the dyno pulls. Cams should flatten out that torque curve.

There's no reason to go with all the head work when you can make an insanely fast, fun car for much less of the cost. Yes, I realize that your car weighs a bit more than the GC6, but that's all the more reason to avoid headwork and retain the bottom end.

I too want to stay N/A, so I respect what you're attempting to do, but I think you're getting ahead of yourself by quite a bit. Besides, you'll notice, as you add more power, that the drivetrain seems to eat up that horsepower and make it dissapear faster than it does the torque.

You can always do the headwork down the road if you decide that bolt-ons and cams aren't enough for you.
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Old 08-31-2005, 09:13 AM   #24
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with $6500 you could really go all out, as in, more than matt suggested. but hey, if you're only looking for 200hp, go with his words. he da man.
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Old 08-31-2005, 09:37 AM   #25
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post some pics of the C!!!

I used to have an ATP 91 G60-T and a 90 G60!
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