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Old 03-03-2004, 07:05 PM   #26
specul8r
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Funny. Here's the reply that I just received from SOA today on the subject:


Subject: RE: Product Information (E-mail #609767) - CHECK WITH TECH 1/26
Date: Wed, 3 Mar 2004 11:03:04 -0500


Hello Dave:

I apologize for the extreme delay in getting back to you. Your
patience is
appreciated. I have received confirmation that the US WRX STi Sedan
pistons
are forged aluminum.

Thanks for the opportunity to be of assistance. If you need any future
assistance, please feel free to contact us.

Best wishes,


Subaru of America, Inc.


-----Original Message-----
From: Subaru of America, Inc.
[mailto:SOAMail@sun.subaru1.com]
Sent: Sunday, January 25, 2004 1:40 PM
To: e-commerce-cds@subaru.com
Subject: Re: Product Information (E-mail #609767) -
CHECK WITH TECH 1/26

SOAMail:



Hi John,

Axis Power Racing just tore down a UDSM 2.5 STi motor, and
had the pistons analyzed. Here's what they said: "It's a cast
hypereutectic
piston. I took it to CP and had them check it out and that's what they
told
me. They couldn't tell if it was hyper or just plain cast but it's def.
not
forged." Can you please check with someone in engineering, and clarify
this
issue for me. I love the car, but need to have correct information. I
bought the vehicle based on information provided at the Subaru website.
Any
information that you can provide will be most appreciated. Keep up the
good
work!






---------------------------------
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Old 03-04-2004, 03:46 AM   #27
john banks
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A typical reply which doesn't address the issues. I thought it was just Brits that got replies like that from our companies
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Old 03-04-2004, 10:50 PM   #28
ANZAC_1915
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Past history has shown the SOA customer service people to try their best but not always be totally accurate.
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Old 03-05-2004, 07:10 AM   #29
TheMadScientist
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Quote:
Originally posted by specul8r
Funny. Here's the reply that I just received from SOA today on the subject:


Subject: RE: Product Information (E-mail #609767) - CHECK WITH TECH 1/26
Date: Wed, 3 Mar 2004 11:03:04 -0500


Hello Dave:

I apologize for the extreme delay in getting back to you. Your
patience is
appreciated. I have received confirmation that the US WRX STi Sedan
pistons
are forged aluminum.

Thanks for the opportunity to be of assistance. If you need any future
assistance, please feel free to contact us.

Best wishes,


Subaru of America, Inc.


-----Original Message-----
From: Subaru of America, Inc.
[mailto:SOAMail@sun.subaru1.com]
Sent: Sunday, January 25, 2004 1:40 PM
To: e-commerce-cds@subaru.com
Subject: Re: Product Information (E-mail #609767) -
CHECK WITH TECH 1/26

SOAMail:



Hi John,

Axis Power Racing just tore down a UDSM 2.5 STi motor, and
had the pistons analyzed. Here's what they said: "It's a cast
hypereutectic
piston. I took it to CP and had them check it out and that's what they
told
me. They couldn't tell if it was hyper or just plain cast but it's def.
not
forged." Can you please check with someone in engineering, and clarify
this
issue for me. I love the car, but need to have correct information. I
bought the vehicle based on information provided at the Subaru website.
Any
information that you can provide will be most appreciated. Keep up the
good
work!






---------------------------------
Asking a customer service rep about thechnical details is never a good idea.
See if he will give you an email to a design or applications engineer for the car.
The question of cast or forged to a customer service rep is like going in to a cell phone store and asking the person behind the counter what WCDMA is.

TMS
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Old 03-16-2004, 09:56 PM   #30
o4whitesti
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My problem with this whole thing is that subaru is either straight false advertising or they are that ignorant about their own product to advertise correctly. I don't plan to add more than 50 hp or so, so as long as the pistons can hold up to that I'll be fine. I am quite surprised to say the least by this whole issue though
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Old 03-17-2004, 02:06 AM   #31
ANZAC_1915
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please stick to the technical details - see first post in thread.
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Old 03-17-2004, 10:19 PM   #32
silverstipa
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Send SOA this link: http://supercompact.gotdns.com/super...rokepiston.jpg

My piston at 4000 miles...300whp on GT30R w/ tuning
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Old 03-18-2004, 10:04 AM   #33
ANZAC_1915
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Why would SOA care about a piston failure on a modified engine?

How you handled the engine management is out of their control.

Please stick to the subject of what is in the car, or the metallurgy.
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Old 03-18-2004, 10:49 AM   #34
silverstipa
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Quote:
Originally posted by Glenn Wallace
Why would SOA care about a piston failure on a modified engine?

How you handled the engine management is out of their control.

Please stick to the subject of what is in the car, or the metallurgy.
Because the damage was mostlikely done prior to the modifications. Detonation caused by the ECU that my dealer refused to reflash. In addition, the post was to determine if the pistons are cast or forged. The picture is for the purpose of answering the original post....therefore it is sticking to the subject. I am sorry if you are unable to see that it is related.

Everyone wants some proof as to the statement of the original post ...forged or not. The picture of my piston IS related to the METALLURGY.

Maybe you need to relax a bit and not be in such a hurry to flame posts that don't conform to your views.
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Old 03-18-2004, 11:33 AM   #35
MJU1983
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Quote:
Originally posted by silverstipa
Because the damage was mostlikely done prior to the modifications. Detonation caused by the ECU that my dealer refused to reflash. In addition, the post was to determine if the pistons are cast or forged. The picture is for the purpose of answering the original post....therefore it is sticking to the subject. I am sorry if you are unable to see that it is related.

Everyone wants some proof as to the statement of the original post ...forged or not. The picture of my piston IS related to the METALLURGY.

Maybe you need to relax a bit and not be in such a hurry to flame posts that don't conform to your views.
Well everyone already knows that all STi pistons JDM and US are cast. So I think the point was just wondering why post pictures of piston failure?

I highly doubt that SOA would replace that under warranty due to your mods.

-Mike
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Old 03-18-2004, 11:55 AM   #36
silverstipa
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Quote:
Originally posted by MJU1983
Well everyone already knows that all STi pistons JDM and US are cast. So I think the point was just wondering why post pictures of piston failure?

I highly doubt that SOA would replace that under warranty due to your mods.

-Mike
No kidding. I never said I was submitting for warranty claim. It was only for educational purposes.

I was only trying to share my experience. When the engine is rebuilt with forged internals and sleeved, I will continue with the mods and testing. I see no need to share my results as it seems everyone already knows everything.
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Old 03-18-2004, 07:43 PM   #37
ANZAC_1915
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Quote:
Originally posted by silverstipa
No kidding. I never said I was submitting for warranty claim. It was only for educational purposes.

I was only trying to share my experience. When the engine is rebuilt with forged internals and sleeved, I will continue with the mods and testing. I see no need to share my results as it seems everyone already knows everything.
Your conclusion that it happened before your mods seems questionable, as does the metalurgy of your picture. If your engine was stock, it might be more interesting.

I suggest you drop this line of "reasoning" in this thread.
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Old 05-15-2004, 10:06 PM   #38
thinimus
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Although this may sound silly, do we know of anyone who has broken a piston on purpose outside of being used in an engine, like smashing it with a sledge and awl for example? Just to see how it breaks and what the grain looks like basically.


Anyway, as for how hypereuteric pistons fare under hard use, many of my racing buddies have said from experience that they are only a smidgen better that regular cast in terms of performance potential.

They make a great oem piston and wear well, but they can't stand near as much impact force as forged when it comes to things such as knock and the like.

Honestly though, for a stock Sti, they make a much better choice.


(I'm assuming that they are hyperueteric.)
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Old 05-24-2004, 03:41 AM   #39
OZ_WHOOSH
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Quote:
Originally posted by MJU1983
Well everyone already knows that all STi pistons JDM and US are cast. So I think the point was just wondering why post pictures of piston failure?

I highly doubt that SOA would replace that under warranty due to your mods.

-Mike
Ah just a quick one.

I don't beleive ALL STi motors run a cast piston.

I currently have 4 2002 STi pistons sitting in my garage, one with a hole in it, along with 1 04 STi and an 04 STi SPEC C piston.

All are forged.

But these are from 2L JDM and OZ spec cars.

I'll see if I can get some pics.
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Old 05-25-2004, 05:22 AM   #40
totoherbs
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Quote:
Originally posted by OZ_WHOOSH
Ah just a quick one.

I don't beleive ALL STi motors run a cast piston.

I currently have 4 2002 STi pistons sitting in my garage, one with a hole in it, along with 1 04 STi and an 04 STi SPEC C piston.

All are forged.

But these are from 2L JDM and OZ spec cars.

I'll see if I can get some pics.
Ver 7 motors have forged pistons. Ver 8s are cast.
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Old 05-25-2004, 09:02 AM   #41
OZ_WHOOSH
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Quote:
Originally posted by totoherbs
Ver 7 motors have forged pistons. Ver 8s are cast.

That's when things get interesting.

Our Version 8 is the 2002 STi, the first bug eye STi we got.

But not the first bug eye WRX.

Our current 2004 is a Version 10.

All OZ spec STi's had Forged pistons.

Some better than others.

We never got the first bug eye STi, which was the Version 7, but I beleive it has the same internals as the Ver 8.
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Old 05-25-2004, 09:56 AM   #42
totoherbs
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Quote:
Originally posted by OZ_WHOOSH
That's when things get interesting.

Our Version 8 is the 2002 STi, the first bug eye STi we got.

But not the first bug eye WRX.

Our current 2004 is a Version 10.

All OZ spec STi's had Forged pistons.

Some better than others.

We never got the first bug eye STi, which was the Version 7, but I beleive it has the same internals as the Ver 8.
Ya, it gets realy tricky... The uk and oz got the ver 7, bug eyes, at the same time, right? The have the ej207 with forged pistons and small port heads. The ver 8 uk, I dont know about OZ, cars still have the same ver 7 small port ej207s with forged piston. That they had in the bug eyes... Not the ver 8 motor they get in japan with cast pistons and large port heads...
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Old 05-25-2004, 08:33 PM   #43
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Quote:
Originally posted by totoherbs
Ya, it gets realy tricky... The uk and oz got the ver 7, bug eyes, at the same time, right? The have the ej207 with forged pistons and small port heads. The ver 8 uk, I dont know about OZ, cars still have the same ver 7 small port ej207s with forged piston. That they had in the bug eyes... Not the ver 8 motor they get in japan with cast pistons and large port heads...
We trailed behind the UK and Europe and never got the Version 7 STi.

Which is a pity.

Our Version 8 was this one, here's a copy of the spec sheet for it, STi 2002

I've had the pistons out of that car, there forged.

I've seen the pistons out of our current 04 STi as well and there forged to.

I hear the pistons in the USDM 2.5 are supposedly better than the forged ones we have but they can be a little fragile.

I ran my 02 STi with 26psi boost for over 12 months without a problem, on the stock internals, with number one piston finally giving out because of a dose of bad fuel.

So there pretty hardy.
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Old 05-28-2004, 10:33 AM   #44
Turismo
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So the BIG question is should forged pistons be fitted to the 2.5 as I have the choice?
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Old 05-28-2004, 11:38 AM   #45
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Quote:
Originally posted by Turismo
So the BIG question is should forged pistons be fitted to the 2.5 as I have the choice?
Yes, its not just that they are cast but they are the weak point of the motor. There are a few threads that talk about the hows and whys....
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Old 05-02-2005, 07:39 PM   #46
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Yes, but HOW MUCH of a weak point?...........are there not some ~500whp STi's with stock bottom ends running around.........?
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Old 05-02-2005, 08:06 PM   #47
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ummmmmmmmmmm.........................this is a year old. you should just start a new thread.
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Old 07-25-2006, 03:49 AM   #48
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News of pistons sti 2006?
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Old 03-20-2007, 02:06 AM   #49
azn_ryder02
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i agree much of this thread doesnt apply anymore NEW THREAD??
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Old 03-20-2007, 04:29 AM   #50
Got Boost?
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I will comment on this and would like to say that I have an 06 sti (USDM) and with 12-13k on a stock motor I had a failure. Broke a ring land on #2 piston and the dealer dismissed it 2 times. So I said f it, and went full stg 4. Guess what ... as soon as I got on the rollers, the problem reared its head. took the car to the dealer where it sits now. SOA is picking up part of the tab and I get stuck with the rest. If indeed they were forged, would I be in this same position? I can tell you that no they are not forged and have a brand new never been rotated set in my possesion.(ordered a new shortblock and picked it up to have some CP forged pistons installed) So this really pisses me off to hear/read about this. My car has been down for a while now,(long story with the dealer), and I am looking forward to being able to drive it again hopefully within the next couple days. The down side, I am out a bunch of cash and have to break in the motor again.
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