(referring to 2008-2009 STi models, but maybe this applies to all 2008+ 2.5L turbo engines)

Quote :

"Subaru has issued an "engineering statement", following criticism of its 2.5-litre engine (used in the Impreza and Forester) on social network sites. Owners on these sites have complained of fragile pistons, which in one case caused £15,000 worth of damage. In its full statement, Subaru said: "You will have been referred to this statement from your contact with several social networking sites. Due to the fact that there has been quite a large amount of inaccurate and misleading comment on a number of these sites, we felt it appropriate from an engineering and technical perspective to outline the design brief of the 2.5 litre Subaru Boxer engine fitted to 2008/2009 Impreza WRX/STI and further explain some facts that will help your understanding. Subaru is an environmentally conscious company that seeks to build products that are thoroughly engineered for the purpose for which they are intended with regard to delivering class leading performance whilst still meeting the very stringent environmental control standards demanded from modern day vehicles; not only by customers but also by the European Union. The Subaru team of Engineers, who we believe to be the most capable and knowledgeable in the business have designed the 2.5 litre unit with lighter weight and lower friction materials, giving higher power without sacrificing current emission and CO2 outputs. The expectation therefore, is that provided the engine is operated within design criteria, using correct fuel grades (97 RON) and serviced within the manufacturer's guidelines, the engine will prove its durability in keeping with Subaru traditions. From a statistical viewpoint, to date 1,044 Subaru Impreza WRX STI 08/09 model year vehicles have been supplied into the UK market through our distribution network and only a small percentage of those have suffered any kind of engine failure. It was recognised very early that a modification to the fuel cut off parameters at maximum engine revolutions was required to reduce impact stresses to the piston land area, therefore an ECU map re-write was introduced on all production vehicles. Also vehicles held in UK stock were modified and a Service Campaign was issued to the UK Subaru network for vehicles already placed in the market. From the information gathered through Fuji Heavy Industries' Engineering Teams, our Regional Service Managers and warranty information, it has been determined that engine failures have occurred due to one, or a combination of the following points: * Engine rev limits being constantly exceeded due to over speeding * Vehicles being un-officially modified outside the design brief of the engine (unit is designed for around 300 BHP or 330 BHP in the case of the STI 330S, not more) * Track use (racing, time trials, rallying etc) * Incorrect maintenance procedures, causing engines to be run with insufficient or contaminated lubricating oils * Use of incorrect fuel grade (RON) * Unofficial "grey" Imports of undetermined specification, ie. not supplied by Subaru (UK) As previously stated, our engines are designed to be operated within the design brief. Where owners have decided to unilaterally modify their vehicles, it can be expected that failures will almost certainly occur. The view taken by our warranty staff has been to investigate thoroughly each case presented, and where evidence is in any way inconclusive, we have always covered those units under the terms of the new vehicle warranty. As customers should rightly expect, the engine will rev freely throughout its complete range, without fault, as long as the points above are observed. You may be aware of a recent joint venture between Subaru (UK) and Cosworth in the development of the Impreza CS400 producing 400 BHP and 375 ft/lbs of torque. This engine has been entirely re-configured from the bottom up to ensure reliability at these power and torque outputs. The high degree of testing and engineering expertise employed by both Subaru (UK) and Cosworth on this project serves to highlight our belief that simply adding performance componentry without an exhaustive development programme will undoubtedly compromise reliability - as other performance tuners have found to their cost. To benchmark the project, a standard WRX STI engine unit was run on a Dynamometer for 50 hours non-stop at varying power and speed settings to replicate the most extreme usage and to highlight any areas of concern; needless to say, no problems became evident despite being operated under these intense conditions. Cosworth Technical Director, Bruce Wood, confirmed the WRX STI OE specification unit passed Coworth's test regime. "We were encouraged that the standard STI engine passed our 50 hour continuous test, which we consider to be rigorous, as this indicated that the starting point for the CS400 programme was suitably robust." Our views are shared by the international motor service community and to present an independent engineering statement from an internationally recognised motor service organisation, MSI Motor Service International GmbH (http://www.ms-motor-service.com) which clearly states the following regarding piston failure: "Material faults are not the reason for ring land fractures, even though they are often the suspected cause. This type of fracture always results from overstressing the material." (Piston Damages - Recognising and Rectifying, section 3.4.4) Our stance is clear and consistent on these issues; where customers are prepared to modify and/or operate their vehicles outside the design parameters, this will invalidate our warranty agreement because it can be expected that failures will occur through no fault of Fuji Heavy Industries or Subaru (UK) in regard to faulty manufacture or improper design, always remembering that the 08/09 STI is designed to be completely reliable at around 300 BHP (and 330 BHP for the STI 330S) but not at 350, 380 or even 400 BHP - power levels at which some owners claim to be running their vehicles. Where any doubt exists, the warranty available through Subaru (UK) is there to support any engine and vehicle defect reported. Should any customer/owner require assistance with engine or indeed any vehicle related issue, the initial approach would be to discuss the problem with your selling/servicing dealer who will involve the services of Subaru (UK) if required. Customer satisfaction is at the heart of everything we do and it is absolutely not in Subaru (UK)'s interest, either financially or reputationally, to decline fair and proper warranty claims. We will not do it. Delivery of excellent customer support is our goal, and our award-winning performance in this area over a period of more than 30 years is no coincidence. We would like to thank you for choosing Subaru and ensure you of our endeavour to make your ownership experience a good one. Subaru (UK) 8 October 2010"

http://www.honestjohn.co.uk/news/legal--motoring-advice/2010-10/subaru-issues-statement-on-impreza-and-forester-25-litre-engines

Of course Subaru is going to tell you not to modify the car, so there's no surprises here. But the fact that they released this statement helps show that the problem does exist even on mildly modified cars.

I'll say it again, if you get a 2008 don't modify it and sell it when the warranty is up.

[Edited on October 13, 2010 at 1:07 PM. Reason : .]

10/13/2010 12:54:38 PM

Quote :

"* Track use (racing, time trials, rallying etc)"

You can't be serious. So what is this car designed for then? Is it for picking up groceries?

10/13/2010 1:02:40 PM

Suboe fail!!!!!

10/13/2010 1:33:25 PM

Subaru makes some junk...with a tacky plastic hood scoop.

10/13/2010 2:12:35 PM

hahahahahaa

you must drive a nissan

10/13/2010 3:15:49 PM

I dont see anything wrong with that statement.

if you beat the shit out of it, dont be surprised if it breaks.

whats new?

almost all cars are like that.

you've just got to be smart about maintenance

10/13/2010 5:29:55 PM

I agree with Subaru. You're going to increase boost to get another 50+ hp and expect everything to work forever? I wouldn't.

You gots to pay to play.

10/13/2010 5:30:18 PM

Yeah I'd say that subie is legit. Although I'd say the real cause is their injectors aren't balanced for shit. Mines is getting some id1000s asap.

10/13/2010 5:55:53 PM

Quote :

"You can't be serious. So what is this car designed for then? Is it for picking up groceries?"

I don't know of many production vehicles that don't void warranties once you put them on the track. Subaru, Mitsubishi, Nissan, Toyota, Ford all have similar clauses. There are models with exceptions but by and large OEM's do everything they can to remove liability for cars being raced in any manner.

Of course, there are some manufacturers that base on other things (GM goes by modifications, which INCLUDE tires), Lotus goes by service intervals, as does Ferrari and Lamborghini.

10/13/2010 9:17:41 PM

Quote :

" I don't know of many production vehicles that don't void warranties once you put them on the track. "

BMW.

They are also ok with mods through approved vendors (dinan). Why I love them



[Edited on October 13, 2010 at 9:59 PM. Reason : k]

10/13/2010 9:55:48 PM

A few points:

Track use does not mean racing, I can't think of any manufacturer who'd warranty the car if raced, that'd be ridiculous. Subaru -of course- won't warranty a raced car.

Dinan is hardly "after market".

I've seen a stripped/caged GT3 on slicks get dropped off @Leith for warranty work, made me so happy. Leith Porsche is often one of the primary sponsors of Porsche Club of America DEs around the east coast, suck on that BMW/Nissan/Subaru + "insert car make here".

That said, let's keep this on topic, NMSJ.

10/14/2010 1:08:15 AM

Japan Makes Some Junk

10/14/2010 1:56:56 AM

I've said it once and I'll say it again... Porsche is the only 100k+ car company I would trust to daily drive.

Porsche has vw reliability. Which may not be great compared to honda and toyota but really beats the shit out of ferrari etc.

And as crappy as that press release sounds I know a friend that had his engine built by a dealer for the cost of his rods and pistons..... Not many companies would throw manley pistons and pauter rods in during a warranty rebuild for blown piston rings. And then hand the guy the factory parts they would use to take home.

10/14/2010 9:10:01 AM

Quote :

"I don't know of many production vehicles that don't void warranties once you put them on the track. Subaru, Mitsubishi, Nissan, Toyota, Ford all have similar clauses. There are models with exceptions but by and large OEM's do everything they can to remove liability for cars being raced in any manner."

The way I read it is that Subaru blames some of the engine failures on the vehicles being "tracked". Attending a driver's education event (in my opinion) should in no way cause engine failure, regardless of under warranty or not. If an engine is properly maintained then 20-30 minute track sessions with the engine under full throttle and near redline shouldn't be conditions in which failure should occur. If that happens that is just junk engineering on the part of the manufacturer.

10/14/2010 11:04:52 AM

Quote :

"The way I read it is that Subaru blames some of the engine failures on the vehicles being "tracked". Attending a driver's education event (in my opinion) should in no way cause engine failure, regardless of under warranty or not"

it doesnt. from what i've read, the engine failures have been sporadic and random on the 08 models. some people hadnt even opened the hood (happened within 500 miles), much less modded it. and there are many many folks on the subie forums whose 08 WRX's and STI's havent had issues at all.

10/14/2010 11:12:50 AM

hah!

ill be damned if the engine is properly maintained during a DE.

the last thing someone with that kind of car wants to do is baby it around the track.

that may be their mentality when they are driving up there to attend, but once you step on track youre a fool if you dont push your car (almost to the limits) to see what it can do.

its not only about redline and full throttle, its redline/full throttle in the turns with lack of oil consumption. thats where most cars blow motors.

heck, 2-3 people (i think, thats what i read on THSCC forums) blew their motors at this years autocross championships because of oil pickup issues. it can happen anywhere, even on the skreet.

10/14/2010 11:15:04 AM

I will reiterate that I think the problem is their fuel injector supplier. I've seen a set of 4 factory injectors have a 15% difference when flow tested. Now if one is 7.5% rich and another is 7.5 percent lean the o2 sensor may read ok but the engine will be knocking like hell regaurdless of pulling timing.

10/14/2010 11:18:12 AM

Quote :

"hah! ill be damned if the engine is properly maintained during a DE. the last thing someone with that kind of car wants to do is baby it around the track. that may be their mentality when they are driving up there to attend, but once you step on track youre a fool if you dont push your car (almost to the limits) to see what it can do. its not only about redline and full throttle, its redline/full throttle in the turns with lack of oil consumption. thats where most cars blow motors."

Huh? Maybe you misunderstood me. By maintenance I mean off track, performed at regular intervals. If your car has an oil pump savenging problem under high G forces that's something you should be aware of before going to the track (i.e. learned from online forums and whatnot). If you're abusing your engine with mechanical overrevs that's your own fault. Driving a car to its limit doesn't mean you're abusing it in any sense.

If it's a sports car (or marketed as such) then it damn well better be designed for full throttle application under high lateral Gs. We're not talking about Toyota Camrys and Chevy Malibus here.

Also, the only engine I've seen blow its load at a track was a 350Z (whose owner claimed he didn't misshift)...NMSJ

[Edited on October 14, 2010 at 11:26 AM. Reason : k]

10/14/2010 11:24:34 AM

Camrys and Malibus.

now thats what im talking about.

this is the same argument you people made about the "glass" transmissions in the WRX when they would launch from 8K RPM's expecting things to hold up.

you people

[Edited on October 14, 2010 at 11:48 AM. Reason : ]

10/14/2010 11:48:13 AM

mahshudduh

10/14/2010 12:02:42 PM

8k hmm? I think that's above redline in any engine Subaru has ever sold in the US.

10/14/2010 12:42:02 PM

Quote :

"I will reiterate that I think the problem is their fuel injector supplier. I've seen a set of 4 factory injectors have a 15% difference when flow tested. Now if one is 7.5% rich and another is 7.5 percent lean the o2 sensor may read ok but the engine will be knocking like hell regaurdless of pulling timing"

Any set of injectors will vary as it ages. There's still a very aggressive 3-stage knock control system on all the modern Subarus plus the factory target air fuel ratio is richer than 11:1. There's also an injector compensation table for each cylinder. I've got a bunch of tables I can post for STi and Legacy right out of ECUflash and Cobb AccessTuner.

Quote :

"this is the same argument you people made about the "glass" transmissions in the WRX when they would launch from 8K RPM's expecting things to hold up."

well big surprise, the STi 6 speeds can be launched hard repeatedly and don't have anywhere near the failure rate of the earlier USDM WRX 5 speed. So the "glass" transmissions look even weaker in comparison to other OEM parts. Even the later WRX and Legacy transmissions are weak compared to the STi six speed.

10/14/2010 12:58:54 PM

^ it's 'STI', not 'STi'

10/14/2010 1:13:37 PM

I consider that a lower case "i"

10/14/2010 1:28:56 PM

I would like your tables sir!! Lol.

I agree with the transmission part. My legacy 5 speed has the same guts as the wrx unit just a stronger case that helps prevent the mesh from separating.

Arghx I'm about to start logging and pretend tuning the lgt via open source. Need wide band and egt before i start doing anything tho.

10/14/2010 1:32:50 PM

^^ nah, its uppercase.

10/14/2010 1:39:48 PM

Who cares?

10/14/2010 1:56:05 PM

obviously, someone who takes the time to carefully capitalize two out of three letters every time they type it.

10/14/2010 1:59:53 PM

Lol true. Funny thing is everywhere subaru types sti that I have found has then all caps.
Aparently I care too. Or im just really bored.

10/14/2010 2:05:01 PM

it's STI

10/14/2010 2:15:05 PM

They officially changed it from STi to STI a few years ago. You Scooby experts should know this

10/14/2010 2:49:47 PM

subaru
trash
inside

10/14/2010 4:38:21 PM

FWIW, Mitsubishi had a similar issue with people blowing up their Evo's. They were even known to goto local tracks/strips and write down the VIN of Evo's they saw racing and voiding their entire warranty.

10/14/2010 5:58:36 PM

they should just do what honda does :

Make a car with so little torque nobody would drag race it anyways.

10/14/2010 6:28:13 PM

just raced an Evo on the way back from dinner. i hit red line TWICE...and pistons didn't even come through my hood. i feel so lucky. i better not red line it again so i can tell this story for the rest of ever.

10/14/2010 7:56:47 PM

wouldn't your pistons come out of your wheels or quarter panel (since it's a flat 4 and all)

10/14/2010 8:08:33 PM

mattjm ftw!!

lol i race 350zs every morn they really don't see it coming.
course... not every legacy has the larger turbo @16lbs too.
no cat back either so its pretty stealth.

10/14/2010 8:15:34 PM

^^ well played sir.

stereotypical piston ejections got the best of me.

10/14/2010 9:18:32 PM

lol

10/14/2010 10:58:05 PM

Quote :

"Dinan is hardly "after market". "

Until few years ago it very much was so. BMW just adopted them. From wiki: Dinan Cars designs and manufactures aftermarket performance parts for BMW and MINI automobiles

BMW supports jacking up boost on N54s it supports FI and all other mods that dinan does without voiding the warranty. Granted you pay through the nose, but at least mfg stands behind the product.

P-cars are another level...

[Edited on October 14, 2010 at 11:24 PM. Reason : f]

10/14/2010 11:24:11 PM

Eh, Dinan has been in agreement w/BMW NA since what 1996? You could buy them through dealers, with dealer support, that's hardly what I'd consider "after market". Also, most of what Dinan sells like over priced exhausts and carbon trim pieces don't exactly do much for performance, or stress placed upon the drivetrain. Big deal they allow you to run another psi of boost. :o Seriously though, let's stop splitting hairs. BMW is not bad about somebody actually driving the car, that's a good thing.

In my view, what Subaru did here was not too bad either. Keep in mind they're the folks who gave away SCCA memberships (or was it NASA) with each WRX sold. Porsche used to do a complimentary Bondurant driving school with each 944 Turbo S sold (I had the paperwork from the one I bought from the original owner!) though nowadays they push their own driving schools.

Also, I call BS on the racing EVO thing, your pistons are probably already broken and you just don't know it yet. It's probably on the side of I40 somewhere along with your IMS from the last Porsche

10/15/2010 1:57:06 AM

Yeah ford supports the 500hp ford racing supercharger for the new mustang too... Ladi friggin da.
Subaru supports spt mods too.

10/15/2010 2:52:02 PM