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Old 11-24-2003, 12:25 AM   #101
singletrack
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Quote:
Originally posted by googe
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.

You people are ridiculous. You don't like it? Take it back.

-st
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Old 11-24-2003, 12:33 AM   #102
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Quote:
Originally posted by singletrack
You people are ridiculous. You don't like it? Take it back.

-st
You say that like its possible.

If I could, I seriously would.
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Old 11-24-2003, 12:38 AM   #103
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Quote:
Originally posted by googe
You say that like its possible.

If I could, I seriously would.
Because of the piston thing?

Or is it something else..
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Old 11-24-2003, 12:41 AM   #104
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Quote:
Originally posted by Invisiguard
Because of the piston thing?

Or is it something else..
Not the piston thing at all to tell you the truth. Although it is disappointing, I made up my mind before that. Its nothing to do with the car itself either actually
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Old 11-24-2003, 02:05 AM   #105
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Quote:
Originally posted by Glenn Wallace
I don't understand what is up with calling the STi short block the Forester XT short block.

Certainly the components are shared, but this engine was designed to be used in many vehicles, and it was important that it have a solid bottom end.

The USDM STi was the first production model with the engine in, so you could say the Forester has an STi 2.5 short block....

A huge amount of work went into engineering the 2.5 STi engine.

New rods, new lightweight cams, new semi-closed deck block with new cast-in main journal technology and dimensions (to increase strength and reduce noise), new material for the cast pistons, new rod bushing material, upgraded big-end bearing material, tapered piston pin boss....

I totally agree that if you want to make a lot of power you will need to upgrade components, but so what?

As far as cost goes:

Aust STi: AUD$56k (US$40k), no DCCD, cast wheels, 261BHP.
US STi: US$31k, DCCD, forged wheels, 300BHP, cast pistons.

Certainly cost was not an issue for selecting the engine components for the US STi.

Glenn
MY SENTIMENTS EXACTLY! Go get em!
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Old 11-24-2003, 10:08 AM   #106
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I wonder if anyone bothered to read the "STI Core Technology" .

It clearly states in the brochure that the US STi uses "Forged Alluminum Alloy Pistons" and "Forged High Carbon Steel Connecting Rods." I really hope I am not the only person that caught this.

It is possible that they are lying. But for some reason or another I highly doubt it.

The above information is available from the Subaru Media Web Site. Click on Impreza Product Info. Then Click on STi Core technology.

Last edited by cjm04WRX; 11-24-2003 at 10:13 AM.
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Old 11-24-2003, 10:15 AM   #107
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Quote:
Originally posted by cjm04WRX
I wonder if anyone bothered to read the "STI Core Technology" .

It clearly states in the brochure that the US STi uses "Forged Alluminum Alloy Pistons" and "Forged High Carbon Steel Connecting Rods." I really hope I am not the only person that caught this.

It is possible that they are lying. But for some reason or another I highly doubt it.

The above information is available from the Subaru Media Web Site. Click on Impreza Product Info. Then Click on STi Core technology.
It's a mistake on the pistons.

-st
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Old 11-24-2003, 11:28 AM   #108
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Quote:
Originally posted by cjm04WRX
I wonder if anyone bothered to read the "STI Core Technology" .

It clearly states in the brochure that the US STi uses "Forged Alluminum Alloy Pistons" and "Forged High Carbon Steel Connecting Rods." I really hope I am not the only person that caught this.

It is possible that they are lying. But for some reason or another I highly doubt it.

The above information is available from the Subaru Media Web Site. Click on Impreza Product Info. Then Click on STi Core technology.
Sir, read the last four pages and look at the pics, we all know what that statement says but they are indeed CAST, of that we are all certain. As for the line from Subarus press Dept, well I dont think it was an intentional untruth, more like the right hand doesnt know what the left hand is doing.
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Old 11-24-2003, 12:14 PM   #109
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i dont like being lied to. and right hand left hand sull***** ( not aimed at anyone) is just that BS. if i said i didnt know my right foot was so heavy, they should still fix any of my problems.
my point- its not MY problem that they cant get something as simple as specs printed out on a comsumer engine.
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Old 11-24-2003, 12:51 PM   #110
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Quote:
Originally posted by googe
You say that like its possible.

If I could, I seriously would.
The car is delivering the EXACT performance that Subaru said it would. But the fact that it doesn't have forged pistons is enough that you would like to get rid of it? My advice to you is to enjoy the fact that you own one of the baddest street legal cars in the world...off the showroom floor.

-st
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Old 11-24-2003, 12:57 PM   #111
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Although your resposes are definately noted. Just stating that thier info is wrong or an error is not enough to convince me that it is incorrect. If infact the pistons are cast then so be it. But what info does everyone have to base this on. Just because they don't look like the older STi forged pistons. If you take a look at a ROSS forged piston all of the forging info is stamped on the bottom of the piston. I which case it makes the bottom of the piston look cast. This topic will not be settled until someone sends one of them off for analysis. There is too much different information coming from one too many sources. Including Subaru themselves.

I honestly don't care what APS or any other so called specialist says. The only person that will be able to settle this topic of discussion is a metalurgist that does a complete analysis of the metal composition and porisity of the metal.

Look I respect APS and thier products. Most of the crap on my car is APS. But the truth be told is that the US STi pistons look very close to forged. But no one on this board is capable of making that determination until a ture analysis is completed or until it comes from the horses mouth. But oh wait. We already have it from the horses mouth. Just no one cares to consider or believe it. Some people just need to put thier slide rulers away and let the experts make the determination. Instead of all of this speculation.

And yes I have read every reply in this thread. I am one of the few people to actually have this short block in a standard WRX and have the car on the road and driving.

Either way it goes. NO ONE really knows what the US STI pistons consist of. But the only literature from Subaru on this topic clearly states that they are Forged Pistons. Personally I think too many people on this board try to hard to be right. And don't try hard enough to really look at everyone elses point of view.

I spent 3 days, putting this motor together, and putting it in my car, in my garage along with V6 STi RA heads. The car runs an APS SR50, APS DR650 FMIC, APS Fuel Rails, APS 3 inch Cat-back, APS BPV, and the rest is Invidia and PDE.

Last edited by cjm04WRX; 11-24-2003 at 01:02 PM.
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Old 11-24-2003, 01:01 PM   #112
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Quote:
Originally posted by singletrack
The car is delivering the EXACT performance that Subaru said it would. But the fact that it doesn't have forged pistons is enough that you would like to get rid of it? My advice to you is to enjoy the fact that you own one of the baddest street legal cars in the world...off the showroom floor.

-st
That doesnt make it any better. Some (alot?) of us didnt buy the car for what it currently does only, but for where we can take it. Why do you think Supras go for so much these days? Not for their 320hp or their mid 13 second ETs The DSMs and EVOs have a very good reputation for their potential as well.

The WRX was a let down, as taking it to 300-320hp destroyed the glass tranny, as many found out.

Anyway, like I said, while it is disappointing that we ended up with a weaker engine than we were told we had, that is not the reason Id take the car back if I could. I paid about 7k or so more for my car than you did.

I still want my forged pistons though
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Old 11-24-2003, 01:29 PM   #113
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In a few months when engine mgmt is available, and bigger turbos start to go in, it will answer some of the questions about weaknesses in the US STI engine.

If the sleeves and the ring lands don't give, we may give the 4G63 guys a run for their money...
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Old 11-24-2003, 01:37 PM   #114
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Quote:
Originally posted by hatchy
In a few months when engine mgmt is available, and bigger turbos start to go in, it will answer some of the questions about weaknesses in the US STI engine.

If the sleeves and the ring lands don't give, we may give the 4G63 guys a run for their money...
I'll be able to see how strong the Short Block is next weekend on the Dyno. Gonna Run the SR50 at 28 psi. everything will be managed by an ECUTek flash.
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Old 11-24-2003, 01:38 PM   #115
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Quote:
Originally posted by cjm04WRX
Although your resposes are definately noted. Just stating that thier info is wrong or an error is not enough to convince me that it is incorrect. If infact the pistons are cast then so be it. But what info does everyone have to base this on. Just because they don't look like the older STi forged pistons. If you take a look at a ROSS forged piston all of the forging info is stamped on the bottom of the piston. I which case it makes the bottom of the piston look cast. This topic will not be settled until someone sends one of them off for analysis. There is too much different information coming from one too many sources. Including Subaru themselves.

I honestly don't care what APS or any other so called specialist says. The only person that will be able to settle this topic of discussion is a metalurgist that does a complete analysis of the metal composition and porisity of the metal.

Look I respect APS and thier products. Most of the crap on my car is APS. But the truth be told is that the US STi pistons look very close to forged. But no one on this board is capable of making that determination until a ture analysis is completed or until it comes from the horses mouth. But oh wait. We already have it from the horses mouth. Just no one cares to consider or believe it. Some people just need to put thier slide rulers away and let the experts make the determination. Instead of all of this speculation.

And yes I have read every reply in this thread. I am one of the few people to actually have this short block in a standard WRX and have the car on the road and driving.

Either way it goes. NO ONE really knows what the US STI pistons consist of. But the only literature from Subaru on this topic clearly states that they are Forged Pistons. Personally I think too many people on this board try to hard to be right. And don't try hard enough to really look at everyone elses point of view.

I spent 3 days, putting this motor together, and putting it in my car, in my garage along with V6 STi RA heads. The car runs an APS SR50, APS DR650 FMIC, APS Fuel Rails, APS 3 inch Cat-back, APS BPV, and the rest is Invidia and PDE.
You belive what you want....

But that facts are the ver8 us and jp have cast pistons. I speeds pages shows the same pistons that in on the aps page, combine that whith rallispecs info; They are hardly forged.....

Quote:
Why do you think Supras go for so much these days?

Arnt the supras pistons hypereutectic cast? Ill have to go do some research on it but I thought they were....
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Old 11-24-2003, 01:40 PM   #116
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Quote:
Originally posted by cjm04WRX
I'll be able to see how strong the Short Block is next weekend on the Dyno. Gonna Run the SR50 at 28 psi. everything will be managed by an ECUTek flash.
Details, please! What injectors are you going to run? What other mods on your car? Now this is exciting stuff!
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Old 11-24-2003, 01:46 PM   #117
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Quote:
Originally posted by totoherbs
Arnt the supras pistons hypereutectic cast? Ill have to go do some research on it but I thought they were....
Yes, I believe they are. My comment was a bit unclear - what I was getting at was that alot of people buy vehicles with the intention of taking them far beyond stock. Supras, DSMs, 4G63s, all have a reputation for having great potential, which is why they are highly sought after by tuners.

That being said, if hypereutectic cast pistons are good enough for them (I am not sure if high hp supras require new pistons or not?) then we may be able to make very high numbers from them also. Alot is uncertain at this point.

However, the fact remains, forged pistons are stronger than cast, and we were told our cars had forged.
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Old 11-24-2003, 01:51 PM   #118
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Quote:
Originally posted by hatchy
Details, please! What injectors are you going to run? What other mods on your car? Now this is exciting stuff!
PE 800's if they come in this week. This will be on C16 fuel. I don;t think the clutch will hold the power but we will see. It is an ACT 2400 WRX clutch. We have been talking to ACT about a stronger pressure plate. Right now the car has PE650's on it. Maybe on full race fuel they will be enough but we will see. At 14.5 PSI the turbo and motor move more air at redline then my old 18G did at 24 psi on the 2.0l. That was good enough for 12.2s @ 114 mph. And Dynoed 348 whp.

We will see though
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Old 11-24-2003, 02:00 PM   #119
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Quote:
Originally posted by cjm04WRX
PE 800's if they come in this week. This will be on C16 fuel. I don;t think the clutch will hold the power but we will see. It is an ACT 2400 WRX clutch. We have been talking to ACT about a stronger pressure plate. Right now the car has PE650's on it. Maybe on full race fuel they will be enough but we will see. At 14.5 PSI the turbo and motor move more air at redline then my old 18G did at 24 psi on the 2.0l. That was good enough for 12.2s @ 114 mph. And Dynoed 348 whp.

We will see though
I'll PM you, I don't want to hijack this most interesting thread :-)
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Old 11-24-2003, 02:31 PM   #120
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the begining of this thread tells me there are too many damn engineers in here!
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Old 11-24-2003, 02:34 PM   #121
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Quote:
Originally posted by googe
Why do you think Supras go for so much these days?
The hypercast pistons?



You are spitting into the wind unless you have proof that the ver 8 STI pistons are in fact inferior to the ver 7.
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Old 11-24-2003, 02:45 PM   #122
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For the fools who think that Forged allways is stronger than cast... just think about it.

I can make a beam that is 1" x1" forged steel... is it going to be stronger than a 1' x 1' cast steel beam? Even if the Forged steel is 144 times stronger its still not as good "strength" wise as it is less stiff and thus will bend more in certain loadings.

My point is that proper design and putting plenty of material in the proper places can make for a stronger piston even using a "weaker" manufacturing technique.
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Old 11-25-2003, 05:55 PM   #123
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bump, this is good information.
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Old 11-25-2003, 09:40 PM   #124
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quote from Quirt in one of the referenced threads:

Quote:
The piston has the apperance of being forged but that is as far as I will go.
another one:

Quote:
The stock STI piston is "very" nice part
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Old 11-25-2003, 10:27 PM   #125
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Quote:
Originally posted by googe

However, ....., and we were told our cars had forged.
Please cite a source for this. Until you can, you need to stop spreading DISinformation, ok?
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