Welcome to the North American Subaru Impreza Owners Club Tuesday January 27, 2015
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 > Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo)

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.
Closed Thread
 
Thread Tools Display Modes
Old 11-21-2003, 09:33 PM   #76
tolnep
Scooby Specialist
 
Member#: 18602
Join Date: May 2002
Location: Planet tolnep
Vehicle:
2005 Moller Skycar
glow in dark purple

Default Re: Re: To APS, others, secrets of the Subie block

Quote:
Originally posted by totoherbs
Have you taken a look at the axis, ispeed, cobb, txs' builder(forget the name) motors.... ?they will be more reilable at the higher powers and wont oval.

As for the 2.0 vs 2.5, I personally think it comes down to what you like, lots of torque or a high reving motor.
2 issues. One they haven't been out very long, except for Cobb. Second the cost for a full long block approaches (I think) 10k for those guys. I have heard good things about I-speed, axis and mangus (spelling?). As for cobb, what they do is a secret and it so expensive that I have not heard anyone talking about the stage III (I think) setup which is a 2.5 complete at over 10,000 dollars. Then of course there is Tony Rigoli who ESX uses. For me 10k for the motor alone is too much. And there doesn't appear to be a lot of people running these full blown 'built' motors. At least ones willing to discuss long term results.

I figure if you go that route, you end up spending about 20,000k maybe more so you are now talking about about 45k in the car and you will never get your money back on a trade or resale. At that amount of money, I would probably buy a Corvette. Although I really like the WRX/STI and my WRX is one of my favorite cars of all time I just cant swallow putting that much money into a car that might end up throwing a rod anyway.. and then what do you do? Spend another 10k? I've done the highly moded car bit with a 240z running a custom built turbo. I put about 25k in the car over a 5 year periiod and it was fun. I only palyed about 3k for the car used and drove it for about 4 years before I started. I spent a lot of time picking the platform and the Z block was really strong and had a long history here in Atlanta of heavy custom turbo setups. But the mod thing got old. There was always another better thing to add, TECII and intercooler, custom headers with two turbos, hand made welded exhaust, corvette brake conversions.. on and on and on. A money pit. I'm old. For me a perfect setup would be if Subie came out with a WRX/STI platform with a 3.x liter turbo 6 pushing around 420HP at the flywheel. When I say WRX/STI platform, I mean I do not need more weight luxury. Just a poor mans porsche turbo. Oh well.. one can hope.
* Registered users of the site do not see these ads.
tolnep is offline  
Old 11-21-2003, 09:38 PM   #77
tolnep
Scooby Specialist
 
Member#: 18602
Join Date: May 2002
Location: Planet tolnep
Vehicle:
2005 Moller Skycar
glow in dark purple

Default

Quote:
Originally posted by singletrack
BWAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA...stop, you're killing me.

-st
Indeed. How bout a million man march on washington to demand our 'truth-in-piston-advertising' reparations.............

Sheese.. maybe I'm lost but I heard those pistons (STI hypertotic or whatever) had advantages over the forged ones. Also, seems I heard porsche uses hypertotoc pistons. Maybe you should just mail your engine back in for a rebate......
tolnep is offline  
Old 11-22-2003, 12:03 AM   #78
totoherbs
Scooby Guru
 
Member#: 7321
Join Date: Jun 2001
Chapter/Region: NESIC
Location: waltham, ma
Vehicle:
.... 122 IggPoints
Work... ahhh... so tired.

Default Re: Re: Re: To APS, others, secrets of the Subie block

Quote:
Originally posted by tolnep
2 issues. One they haven't been out very long, except for Cobb. Second the cost for a full long block approaches (I think) 10k for those guys. I have heard good things about I-speed, axis and mangus (spelling?). As for cobb, what they do is a secret and it so expensive that I have not heard anyone talking about the stage III (I think) setup which is a 2.5 complete at over 10,000 dollars. Then of course there is Tony Rigoli who ESX uses. For me 10k for the motor alone is too much. And there doesn't appear to be a lot of people running these full blown 'built' motors. At least ones willing to discuss long term results.

I figure if you go that route, you end up spending about 20,000k maybe more so you are now talking about about 45k in the car and you will never get your money back on a trade or resale. At that amount of money, I would probably buy a Corvette. Although I really like the WRX/STI and my WRX is one of my favorite cars of all time I just cant swallow putting that much money into a car that might end up throwing a rod anyway.. and then what do you do? Spend another 10k? I've done the highly moded car bit with a 240z running a custom built turbo. I put about


25k in the car over a 5 year periiod and it was fun. I only palyed about 3k for the car used and drove it for about 4 years before I started. I spent a lot of time picking the platform and the Z block was really strong and had a long history here in Atlanta of heavy custom turbo setups. But the mod thing got old. There was always another better thing to add, TECII and intercooler, custom headers with two turbos, hand made welded exhaust, corvette brake conversions.. on and on and on. A money pit. I'm old. For me a perfect setup would be if Subie came out with a WRX/STI platform with a 3.x liter turbo 6 pushing around 420HP at the flywheel. When I say WRX/STI platform, I mean I do not need more weight luxury. Just a poor mans porsche turbo. Oh well.. one can hope.


I agree with the cost, but thats the price to play with the big power. I think 420hp should be no problem with the sti block... people are doing 300+ with the much weaker wrx block.

Quote:
Sheese.. maybe I'm lost but I heard those pistons (STI hypertotic or whatever) had advantages over the forged ones. Also, seems I heard porsche uses hypertotoc pistons. Maybe you should just mail your engine back in for a rebate......
Ya they have there advantages, I would rather have them in a stock block, but the cast is still not as strong; and I dont see any one complaining about thier blocks....
totoherbs is offline  
Old 11-22-2003, 02:17 AM   #79
ANZAC_1915
Moderator
 
Member#: 456
Join Date: Oct 1999
Chapter/Region: NWIC
Location: Redmond, WA, USA
Vehicle:
2008 Forester XT
Steel Gray Metallic

Default

Quote:
Originally posted by n2xlr8n
"IMHO The one thing I do notice about the USDM STI piston is its smaller thickness from the top of the piston to the first ring land. This alone says its not as strong."


That would be known as compression height...it has nothing to do with strength. The reason there is a difference between the two in that regard relates to stroke and rod length.

.0015"........hmmmm. Noted.


Steve
Actually FHI considers the reduced compression height (notwithstanding what it contributes to the motor's compression ratio) to be a durability feature of the new piston design.

Glenn
ANZAC_1915 is offline  
Old 11-22-2003, 02:51 AM   #80
Turbo Dave
Scooby Newbie
 
Member#: 45743
Join Date: Oct 2003
Default

Guys, we surrender, O.K?!!

Your hypereutectic pistons are absolutely great, all right?!!

We do not sell pistons and only posted the photos in an attempt to explain why we shall run conservative boost numbers on our customer's (as opposed to our own) STi's. As , in fact, we do on WRX's, equipped with a similar piston. That's all!! We did NOT want an arguement!! Really!!

I shall attempt to answer as many specific questions as I can and then shall not be back here.

Please feel free to send any further queries dirctly to us at work, as a number of you have already done.

1) No Subaru USA literature I have ever seen, ( and I have a good collection) has ever claimed the US Spec STi pistons are forged.

2) StrangerQ: Not trying to blow off ANY question! As if I would!! You just were not specific enough with your question. Please reframe it more specifically and send it to me at work. So long as I can follow what you are asking, I shall be happy to address it for you.

3) ROYBFR: I do not think $1022.00 is expensive for a set of FORGED pistons, at all. I did not say that, so cannot understand your comments. Actually, for a set of genuine STi, forged, version 7/8, 2 Litre pistons, it is VERY reasonable. I was talking about $1022.00 being expensive for CAST pistons, hypereutectic or not and I think I shall stick to that assesment!

Oh, re the turbo pricing. It is a similar situation. $1,600 to $2,000 for a low volume, custom turbo, is also reasonable. However, for a high volume, mass produced piece, it would be ridiculous!

4) DWX: And you are kidding yourself if you think:-
a) ANY casting is as strong as an equivilent forged component
b) A mass production, assembly line Forrester short is as
durable as a genuine STi version 7/8 short.

5) Daytona: Just check with your local Subaru dealer. One phone call and you will discover for yourself that the piston P/N number for US spec Forrester and STi are identical.

6) Todd Stratton: The most important change to the 2 Litre Version7/8 bottom end, intended to address the version 6 (and earlier) big end problems to which you rightly refer, was to re-index and cross drill the crankshaft oil holes. Two items conspicuous by their absence in the US Spec 2.5 Litre STi, I might add!!

However, let's not start talking about the stock, normally aspirated 2.5 Litre crank, used in the US spec STi's shall we?!! It will just start another confrontation, which we REALLY do not want!!!

As I said at the start, we surrender!! Any further queries, direct to work, PLEASE!!


Dave
APS
Turbo Dave is offline  
Old 11-22-2003, 01:09 PM   #81
Jon [in CT]
*** Banned ***
 
Member#: 2992
Join Date: Nov 2000
Chapter/Region: NESIC
Location: Connecticut, USA
Vehicle:
02 WRX Sedan
Silver

Default

Quote:
Originally posted by Turbo Dave
1) No Subaru USA literature I have ever seen, ( and I have a good collection) has ever claimed the US Spec STi pistons are forged.
If one begins at media.subaru.com, clicks on Impreza in the Product Info section, and then opens the document titled STi Core Technology, one finds this paragraph on page 2:
Quote:
A stiffer engine block was necessary to provide durability under higher boost and power conditions. The 2.5-liter horizontally opposed (boxer) 4-cylinder engine is based on a specially reinforced semi-closed deck engine block with forged aluminum alloy pistons and forged high-carbon steel connecting rods. A semi-closed deck design provides the same cooling efficiency as an open-deck cylinder block but with the greater strength of a full closed-deck. Special reinforcing ribs in the block provide additional strength.
I believe that document formed part of the Press Kit that SOA distributed at STi "Ride and Drive" events for the media.

On the other hand, no Subaru of America literature that I've seen has ever stated that the US STi's pistons are cast.

Last edited by Jon [in CT]; 11-22-2003 at 01:41 PM.
Jon [in CT] is offline  
Old 11-22-2003, 01:25 PM   #82
modvp
Scooby Specialist
 
Member#: 25215
Join Date: Sep 2002
Location: MD
Default

Honestly, I think Subaru made a mistake in saying the USDM sti pictures are forged. One can clearly see from the pictures shown to us by APS that the sti pistons are not forged! Moreover, car companies do not make niche cars for the US market. Anything we get comes with the assumption of mass production…cheap.
modvp is offline  
Old 11-22-2003, 01:45 PM   #83
Daytona
Scooby Newbie
 
Member#: 39468
Join Date: Jul 2003
Chapter/Region: TXIC
Location: Houston
Vehicle:
2004 STi
Blue/Silver

Default

Who thinks that forged components are, by definition, not mass produced? That is ridiculous, the con-rods are forged, as is the crank and those are all mass produced. I would certainly like to think that my STi motor has been dynamically balanced to some degree from the factory, and since most ppl's baseline dynos are incredibly close, I would say that some amount of special attention has been given to these motors.

Honestly, American V8's, which dominated the WORLD in power-production were sure as heck mass produced for their 30 plus years of dominance...if you want a hand-built vehicle, get an NSX, you KNOW that the Subaru is cheap, that is why you bought it. Quit kidding yourselves here!
Daytona is offline  
Old 11-22-2003, 01:56 PM   #84
strangerq
Scooby Specialist
 
Member#: 13095
Join Date: Dec 2001
Default

Quote:
Originally posted by Turbo Dave
[b] Guys, we surrender, O.K?!!

Your hypereutectic pistons are absolutely great, all right?!!

Dave this has been a very good thread, and I am glad you started it. But climb off the high horse ok? The problem only began because you insisted that cast pistons were unique to the USDM STI. You were clearly wrong. No harm no foul. But if anyone is being stubborn about something it is you on this point.


Quote:
That's all!! We did NOT want an arguement!! Really!!
You protest too much.

Quote:
1) No Subaru USA literature I have ever seen, ( and I have a good collection) has ever claimed the US Spec STi pistons are forged.
Yeah they did, but it is now clear that they were mistaken. Understandable, as you were also mistaken about the Ver 8's which are also cast. No big deal, imho.

Quote:
2) You just were not specific enough with your question. Please reframe it more specifically and send it to me at work.
Dude please. I asked you how you can on the one hand - brag about how much power you are making on the USDM engine (essentially 500 hp on typical stage 2 mods (!) ), and on the other, bag on the engine as being too weak to handle said power. End the double talk, and stop trying to have it both ways.


Quote:
3) ROYBFR: I do not think $1022.00 is expensive for a set of FORGED pistons, at all. I did not say that, so cannot understand your comments. Actually, for a set of genuine STi, forged, version 7/8, 2 Litre pistons, it is VERY reasonable. I was talking about $1022.00 being expensive for CAST pistons, hypereutectic or not and I think I shall stick to that assesment!
Dude reread the thread. That is not what you said. You denied that the pistons were cast. You claimed cast pistons were cheaper. I pointed out that the forged ver. 7's cost the same as the cast ver 8's. (on rallispec's site)..... You then countered by suggesting they were way overpriced at any rate.... You called it a pricing error (whatever) and suggested that therefore we could not be sure the piston's were cast, as that could also be an error.


In summation: There is a reason why many different people are having a problem with the things you are saying. You should review some of your comments and reconsider them.

Anyway, good thread, best of luck, and I look forward to hearing more news from APS.

Last edited by strangerq; 11-22-2003 at 03:03 PM.
strangerq is offline  
Old 11-22-2003, 02:41 PM   #85
hatchy
Scooby Specialist
 
Member#: 36852
Join Date: May 2003
Location: North West
Vehicle:
2004 STI

Default

I don't know about you, but I am thankful we got the cheap 2.5L STi over the hand built, too-good-for-Americans 2.0L race motor. It runs cleaner, and will probably outlast the 2.0L motors.

If hypereurectic pistons are good enough for Porsche, Supra, evo, etc, it is good enough for me.

Mass production doesn't always mean cheap, it is pretty much a requirement for companies if they want to sell a product successfully here. Besides, I like machine built stuff, it takes the error-prone human element out.

Quote:
Originally posted by modvp
Honestly, I think Subaru made a mistake in saying the USDM sti pictures are forged. One can clearly see from the pictures shown to us by APS that the sti pistons are not forged! Moreover, car companies do not make niche cars for the US market. Anything we get comes with the assumption of mass production…cheap.
hatchy is offline  
Old 11-22-2003, 03:08 PM   #86
Daytona
Scooby Newbie
 
Member#: 39468
Join Date: Jul 2003
Chapter/Region: TXIC
Location: Houston
Vehicle:
2004 STi
Blue/Silver

Default

Don't forget good enough for WRC...
Daytona is offline  
Old 11-22-2003, 03:44 PM   #87
Z1 Performance
Former Vendor
 
Member#: 9327
Join Date: Aug 2001
Location: Z1Auto.com
Default

Geez....this forum is just nuts lately

Nearly every production car on the planet uses hypereurectic pistons. Simple put, theya re high pressure cast pistons, and just about every Japanese car that has pistons for the last 10 years at least has had 'em. Just because something is "forged" does not mean it is better. Just becuase something might technically be classified as cast, does not mean its inferior. Metallurgy (sp?) comes into play big time.

As for all these "exotiv" parts Subaru uses - they are not exotic at all, and are in fact mass produced. Does this make it bad - not at all. Does it means it can be improved upon? Sometimes, yes, sometimes no.

I honestly would not sweat it one way or another. Subaru is a company like any other, and as such, is subject to marketing tools..poetic justice if you will

If your goal is reliability, keep the boost in check, the fuel in check, and know what you're doing with the tuning...far more important than stressing over the silicon content your pistons have

Adam

Last edited by Z1 Performance; 11-22-2003 at 03:55 PM.
Z1 Performance is offline  
Old 11-22-2003, 10:25 PM   #88
modvp
Scooby Specialist
 
Member#: 25215
Join Date: Sep 2002
Location: MD
Default

Quote:
Originally posted by hatchy
I don't know about you, but I am thankful we got the cheap 2.5L STi over the hand built, too-good-for-Americans 2.0L race motor. It runs cleaner, and will probably outlast the 2.0L motors.

If hypereurectic pistons are good enough for Porsche, Supra, evo, etc, it is good enough for me.

Mass production doesn't always mean cheap, it is pretty much a requirement for companies if they want to sell a product successfully here. Besides, I like machine built stuff, it takes the error-prone human element out.

Cheap does not always means quality. I don't think anyone is saying that the quality of the Sti is second standard. In production, if one can save a few pennies here and there, it can add up to huge sums in savings.
modvp is offline  
Old 11-22-2003, 11:21 PM   #89
Jon [in CT]
*** Banned ***
 
Member#: 2992
Join Date: Nov 2000
Chapter/Region: NESIC
Location: Connecticut, USA
Vehicle:
02 WRX Sedan
Silver

Default

Quote:
Originally posted by modvp
Cheap does not always means quality. I don't think anyone is saying that the quality of the Sti is second standard.
APS is, in fact, saying the US STi's pistons are "second standard."
Jon [in CT] is offline  
Old 11-23-2003, 03:04 AM   #90
XT6Wagon
Scooby Specialist
 
Member#: 524
Join Date: Nov 1999
Location: WA
Vehicle:
04 STi
White

Default

Too bad that APS DAVE is so full of it, they clorox the clippers after they cut his hair.

Simply a off the wall reaction by someone who isn't technicly inclined and has little in the way of a grasp of the realities of a modern performance engine.
XT6Wagon is offline  
Old 11-23-2003, 04:20 AM   #91
Invisiguard
Scooby Specialist
 
Member#: 43201
Join Date: Sep 2003
Location: SF Bay Area
Vehicle:
04 STi
07 Corvette

Default

Quote:
Originally posted by hatchy
I don't know about you, but I am thankful we got the cheap 2.5L STi over the hand built, too-good-for-Americans 2.0L race motor. It runs cleaner, and will probably outlast the 2.0L motors.

If hypereurectic pistons are good enough for Porsche, Supra, evo, etc, it is good enough for me.

Mass production doesn't always mean cheap, it is pretty much a requirement for companies if they want to sell a product successfully here. Besides, I like machine built stuff, it takes the error-prone human element out.
Since it seems that no one has stated it clearly yet, let me be the first.

Hypereurectic pistons are niether as good or as bad as you might come to belive by reading this entire post. Hypereurectic simply means high silicon content. Silicon is added to aluminum alloy to make it stronger and it can also be heat treated to a desired hardness. But just as adding high carbon content to steel, you can ultimately compromise its stregnth. Simply put, car makers use hypereurectic casts because you can get them to perform extremely reliable within a certain operational range, and since the engineers are designing these engines to work reliably at a very specific range, when cost becomes a large factor the hypereurectics become a no-brainer. So although not as ideal as a forged piston, a hypereurectic is the best COMPROMISE for automakers.

Imagine you have 2 razor blades, make one with a twice the carbon content/hardness and under identical operational stress it will remain twice as sharp for twice as long as the lower carbon blade, but increase the operational stress and the stregnth of the sharper blade is quickly compromised. Thats the best half-assed example I can think ofright now but you get the point, I talk alot better than I type
Invisiguard is offline  
Old 11-23-2003, 11:38 AM   #92
tolnep
Scooby Specialist
 
Member#: 18602
Join Date: May 2002
Location: Planet tolnep
Vehicle:
2005 Moller Skycar
glow in dark purple

Default

quote:
A stiffer engine block was necessary to provide durability under higher boost and power conditions. The 2.5-liter horizontally opposed (boxer) 4-cylinder engine is based on a specially reinforced semi-closed deck engine block with forged aluminum alloy pistons and forged high-carbon steel connecting rods. A semi-closed deck design provides the same cooling efficiency as an open-deck cylinder block but with the greater strength of a full closed-deck. Special reinforcing ribs in the block provide additional strength.

.....

Anyone care to comment on this info about the 2.5 block. Did they lie there too? Is it trully reinforced with 'special ribs'
tolnep is offline  
Old 11-23-2003, 12:19 PM   #93
strangerq
Scooby Specialist
 
Member#: 13095
Join Date: Dec 2001
Default

I don't think it's reasonable to imply that Subaru or anyone else lied about forged pistons.

Again...they publicly stated that the STI's were switching to hypercast pistons for 2003 before the USDM car was even released. This pertained to the rally cars!

So many people made the honest mistake of assuming that STI's would continue on with forged pistons, because they had in previous years.

Dave of APS himself made that mistake- regarding the version 8 pistons (JDM). 1st insisting they were forged, then excusing himself from the conversation.

This is really about outdated information.

If you guys ever find any real info to suggest that the new hypercast pistons are too weak for - whatever application, pls. let me know. Until then, I'm going back to bed. insert :snoreicon:



strangerq is offline  
Old 11-23-2003, 01:40 PM   #94
dwx
Scooby Guru
 
Member#: 8343
Join Date: Jul 2001
Chapter/Region: MWSOC
Location: Atlanta, GA
Vehicle:
2005 2012 Jeep
2013 DGM BRZ

Default

I'm not sure if Dave is still reading this thread or not. I apologize if this thread has turned into people attacking APS and yourself but you keep failing to realize it's not a "our motor versus your motor" argument. You kept turning it into that, and that's not what it's about. I never said the 2L shortblock was stronger or weaker than the 2.5L, I just corrected some factual information you were incorrect about.

Ron at Axis has taken apart several JDM 2L engines. There are a number of differences in them both internally and externally to the V7 STI engines (Aus/International spec V8 motor). Subaru definitely changed things with the new JDM twin-scroll motor, including the crank, bearings, and the rods I believe. Ron would know better than I would.

User Sponaugle on this board mainly tracks his car and has had motor failures with STI 2L motors. Just look on the UK or your own Australian boards, STI engines do break.
dwx is offline  
Old 11-23-2003, 01:48 PM   #95
googe
Scooby Newbie
 
Member#: 42066
Join Date: Aug 2003
Location: WA
Default

Quote:
Originally posted by Jon [in CT]
If one begins at media.subaru.com, clicks on Impreza in the Product Info section, and then opens the document titled STi Core Technology, one finds this paragraph on page 2:I believe that document formed part of the Press Kit that SOA distributed at STi "Ride and Drive" events for the media.

On the other hand, no Subaru of America literature that I've seen has ever stated that the US STi's pistons are cast.
I knew I read that somewhere. Looks like Subaru will be sending me a new set of FORGED pistons, just like they said they were doing when they were telling me what I would get when I purchased my car.

googe is offline  
Old 11-23-2003, 02:03 PM   #96
XT6Wagon
Scooby Specialist
 
Member#: 524
Join Date: Nov 1999
Location: WA
Vehicle:
04 STi
White

Default

DWX, Attacking Dave? How about DAVE posting garbage of little use to us? HE is a technophobe who is afraid of changes and so lashes out at them. He can't understand why our NON-Forged pistons are far better than the old forged ones, and its not that they are cheaper. It might be that the detonation resistance of the pistons is reduced, but all the other advantages greatly out wiegh that.

In fact from the ACTUAL techincal data posted by people I would agree on the 120% stronger bit. It appears the entire piston was redesigned and used a heavier construction where needed to make it stronger.


Also his rants on the "mass produced junk" that is the EJ257 is way off base. I would think that there is 0 people here who would take a Standard hand built STi Version 1 EJ20 over the mass produced EJ257.... Because the Version 1 motor is complete garbage in comparison. Cast pistons, worthless headgaskets, almost horrible heads, hydrualic lifters, etc. If having the same motor in my STi as the Forester XT and legacy turbos is the price I have to pay to get better heads, better cams, better shortblock, better TB, etc.. Who am i to complain. Also if it DOES puke... They will be 10X more common so much much cheaper to pick up a used one.
XT6Wagon is offline  
Old 11-23-2003, 07:32 PM   #97
modvp
Scooby Specialist
 
Member#: 25215
Join Date: Sep 2002
Location: MD
Default

I take it that allot of Sti owners are not fond of APS...true?
modvp is offline  
Old 11-23-2003, 08:07 PM   #98
Invisiguard
Scooby Specialist
 
Member#: 43201
Join Date: Sep 2003
Location: SF Bay Area
Vehicle:
04 STi
07 Corvette

Default

Quote:
Originally posted by modvp
I take it that allot of Sti owners are not fond of APS...true?
Actually up till now I had not heard anything at all bad about APS on this forum, they have been modding and racing Subes for years, and I think that last statement about our hyperutectic cast pistons being "far better" than forged ones are wildly optimistic, to say the least. Im not going to add more fuel to this firestorm, suffice it to say the evidence for hyperutectic cast vs. forged pistons has been known and well documented for years by engine builders and others in the racing community. Hell, just go on a Mustang Forum and ask how popular hyperutectic pistons were when Ford started putting them into their 5.0s in the 90s, nothing but headaches. Anyhow, I'll leave it at that. If you dont belive me than just get off this thread and do a search on google and educate yourself, the info is all there.

Last edited by Invisiguard; 11-23-2003 at 08:15 PM.
Invisiguard is offline  
Old 11-23-2003, 09:28 PM   #99
Templar
Scooby Specialist
 
Member#: 483
Join Date: Nov 1999
Chapter/Region: South East
Location: A twisty road not near you.
Vehicle:
2010 RSV4
Aprilia Racing Black

Default

A very interesting thread...

Not very informative but interesting.

I don't even know where to begin, but I think that I have to start somewhere to put all the correct information down. I guess I will start with the piston info:

1. The US STI engine uses Hypereurectic Pistons. This are much stronger than a standard cast piston (especially the standard Subaru cast pistons)

2. All overseas STI versions up through the version 7 used forged pistons.

3. All overseas STI version 8 (RA and Spec C included) use Hypereurectic cast pistons.

4. All standard WRX 2.0 (US and overseas) models use standard cast pistons.

5. I am not certain of APS's basic verbal abuse of the USDM EJ257 engine. The block itself is not going to be as strong as the overseas STI blocks (simply due to piston wall thickness if nothing else), however the crank, rods and pistons have been previously examined by several other tuners (one of them being Quirt Crawford who has many years of experience and is responsible for the fastest 4 cylinder car in the world) and these parts have been declared as very high quality. Here is a great thread about the shortblock.

6. Despite number 5, I know that APS builds great stuff for the various EJ engines, and they have made more power from the EJ257 than anyone else at this point.

7. To the best of my knowledge the only "hand built" portion of any of the overseas STIs is the hand porting of the heads on the RA, spec C and limited cars. I could be mistaken, but all the literature and info I have leads to that conclusion. These heads are also vastly superior to the heads on the US STI.

8. So far, I have only heard of the failing of one engine part in a US STI. This was the rod bearings, and I have seen several overseas STI engines that have also spun their rod bearings as well.

9. No matter what the concerns are with the EJ257 (US STI block) the engine, when properly tuned, is capable of way more power than practically any of us will even try to get out of it.

10. Remember, there are plenty of 600 horsepower Supras out there with "a high volume, mass produced piece."
Templar is offline  
Old 11-24-2003, 12:38 AM   #100
totoherbs
Scooby Guru
 
Member#: 7321
Join Date: Jun 2001
Chapter/Region: NESIC
Location: waltham, ma
Vehicle:
.... 122 IggPoints
Work... ahhh... so tired.

Default

Quote:
Originally posted by tolnep
quote:
A stiffer engine block was necessary to provide durability under higher boost and power conditions. The 2.5-liter horizontally opposed (boxer) 4-cylinder engine is based on a specially reinforced semi-closed deck engine block with forged aluminum alloy pistons and forged high-carbon steel connecting rods. A semi-closed deck design provides the same cooling efficiency as an open-deck cylinder block but with the greater strength of a full closed-deck. Special reinforcing ribs in the block provide additional strength.

.....

Anyone care to comment on this info about the 2.5 block. Did they lie there too? Is it trully reinforced with 'special ribs'
No, if you look at the i speed page I posed you will see pics of the block and the "ribs" subaru is talking about. I have no idea why they say the sti has forged..... All I can think is the arm doesnt talk to the head directly. Someone in the tec department didnt inform the media department.

Quote:
Originally posted by modvp
I take it that allot of Sti owners are not fond of APS...true?
I like aps they have great but somewhat costly parts, one the other hand Dave thinks everything is about him.....

Quote:
Originally posted by Turbo Dave
Guys, we surrender, O.K?!!

Your hypereutectic pistons are absolutely great, all right?!!
Give what up? This wasnt about winning, it was about finding out information.
totoherbs is offline  
Closed Thread

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
FS: 2.5L STi Block with CP Forged Pistons Suby_06_STI RMIC Private Classifieds 9 03-23-2009 01:32 PM
Version 8 turbo kit, 2.5L CP pistons, sti block, wrx heads jermany755 Engine/Power/Exhaust 8 09-26-2008 01:54 PM
a realistic compression for 07 sti 2.5L FORGED PISTONS jhook Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 1 08-04-2008 09:58 AM
FS: Rays Engineering Volks TE37 White , ej207 shortblock, 2.5L sti pistons, kvr rotor GC8_SpecC VIC Private Classifieds 3 09-11-2007 02:42 AM
FS: 4 2.5l Sti pistons Turbo4me North West Impreza Club Forum -- NWIC 8 09-16-2004 07:28 PM


All times are GMT -4. The time now is 05:18 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.