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Old 12-29-2020, 02:16 PM   #1
Whitenukl
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Default Ej25 still problematic?

Ill make this as short as possible. Been 4 yrs since Ive been on this page but I used to have a 07 hawkeye and loved it. Sold it, never touched Subi again. Thinking about getting back into a 2018
STI. Im familiar with the knock and reliability issues with the ej25 motors. Question is....did Subi fix this in 2018? Most issues Ive seen are up to 2017 models. Any feedback or links where I can read and do my research would be helpful as well. Thanks
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Old 12-29-2020, 06:27 PM   #2
snow_bound26
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Asking this as a serious question, why do you think these engines are problematic? Yes I know the reputation, but typically it's user error not because Subaru made them sub par. And yes I've been in the Subaru game for many years now and do modify mine.
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Old 12-29-2020, 06:54 PM   #3
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I agree, Fragile maybe, problematic no. If you understand the engine, how to mod properly, know how to drive, and remember to change/check your oil. You should be fine
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Old 12-29-2020, 07:24 PM   #4
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Originally Posted by snow_bound26 View Post
Asking this as a serious question, why do you think these engines are problematic? Yes I know the reputation, but typically it's user error not because Subaru made them sub par. And yes I've been in the Subaru game for many years now and do modify mine.
Fair enough. When I say ďproblematicĒ, I mean prone to failure. Of course if you donít know the correct mods and get an accurate tune for those mods, your setting yourself up for problems. Or if you drive it like a raped ape, youíll eventually run outta luck. But Iíve read many stories of stock ej25ís having issues from regular daily driving. (Again Iím taking face value that all of those people arenít driving the piss out of it too). Just gauging some feedback from the community is all. I appreciate it
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Old 12-29-2020, 07:25 PM   #5
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I agree, Fragile maybe, problematic no. If you understand the engine, how to mod properly, know how to drive, and remember to change/check your oil. You should be fine
Fragile is a good word to use. Thats what I should have gone with. Thanks for the feedback
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Old 12-29-2020, 09:02 PM   #6
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I don't have the specs in front of me but I doubt Subaru opened up the ring gaps in later EJ257s so the chances of a ring land failure under the right conditions are probably still there.

Rod bearing issues on 2012-2017 STIs are hopefully a non-issue on 2018+. I'd still run T6 or better oil...

At some point you'd probably want to put in a Killer B oil pickup regardless.
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Old 12-29-2020, 10:43 PM   #7
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Default Ej25 still problematic?

From what I've read, 2019+ have the same specs as the type RA block and has been proven to hold more power easier.

Reality is all car manufacturers have some cars that are lemons out of the factory, but these days that's few and far between. A lot of the issues with 2004 and newer 257s is people do beat the piss out of them more than they admit and then blame it on Subaru. Ringland failure being one of the most common is all about understanding when to hold back on the power and having a really good tune when you're walking that line.

Are you planning on modding a car that's new enough to still have a fair amount of warranty left? If not, then use quality oil and gas, do routine maintenance and don't beat the piss out of it. If you are planning on modding it right away, then read up about it and understand where that line is. Get a damn good tuner and do what they tell you to and as long as you don't beat the piss out of it and do proper maintenance you'll most likely be fine.

And +1 for the Killer B pick up. Always a good idea. I'd do the baffle while you're in there as well.
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Old 12-29-2020, 11:36 PM   #8
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I appreciate the feedback. It only had 11k on the clock so no mods for me yet. Previous owner put a Cobb intake on it already so that will stay in place for now. Not doing it like my last Subie...if I do mod it, It will be a simple exhaust, access port and a good tune. Def will look into the killer b and keep the T6 fresh. Thanks everyone

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Old 12-31-2020, 10:21 AM   #9
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I think there are some years that have a higher incidence of bottom end issues - unmodified, well maintained, and unabused, and still a small percentage are spinning bearings - enough that there was a class action suit that Subaru lost.
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Old 12-31-2020, 10:54 AM   #10
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Have to agree, it's all in how you take care of the set up.

My new ej257 shortblock I installed in my 2005 Legacy GT wagon back in May 2012, now has over 140,000 trouble free miles running on Amsoil 5w-40 European Classic and their EA15K13 filters doing 7000+ mile oil changes. Blackstone Labs told me the oil is fine at 7000 miles.

Car has been on Cobb AP since it first came out for Legacy GT's back in Dec 2004. Has been tuned at 21psi on stock fueling since Aug 2011 with a vf52.
The engine has none of the Subaru cold engine noises.

The car is driven for long distance, us high mileage long term GT owners have learned these engines need to be driven for distance, they don't do well when only driven a couple miles and shut off. Also, get the car off the factory Tune as fast as possible.
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Old 12-31-2020, 11:52 AM   #11
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I'd recommend you realign your logic:

1. The premise that there is/was systemic issues with EJ motors is false.
2. The premise that the EJ motor is perfect is false.
3. The premise that any motor is perfect is false.

The idea that there is a perfect car, other than the Mercury Marauder, is crap. So every car purchase has a certain amount of belly butterflies. If you want a new Subaru, get one. Want some more peace of mind? Get an extended warranty and/or don't mod it. If you want a used Subaru, get one. Get a prepurchase inspection for ~$200 to include a compression/leakdown. Get a stock one and if modded, ensure your prepurchase inspector is Subaru mod familiar or you are. Perform a maintenance check via receipts or your local Subaru dealership as to maintenance and if acceptable or unknown, perform all maintenance to bring it up to the current mileage baseline. Get to know your motor's oil consumption...some EJs sip oil, some don't....after 3 months of ownership and weekly checks, you should know your motor's cycle....keep up with it. And in all cases, do not drive like a jackwagon! The biggest killer of Subarus we aren't talking about enough is people stomping on the gas pedal with the Wrath of Khan in gears 5 and/or 6.

And live your life. Somewhere someone out there is mad that their Rolls-Royce Cullinan is down for repairs. How are you different?
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Old 01-02-2021, 06:32 AM   #12
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If nothing else, I'd say all the 'issues' are known. That's one reason I still bought a 2020 STI; it's like... really old. The stuff is insanely well documented, and it 'just works'; or if it doesn't work, someone has a 5 year old (or 10 year old) blog post about how to fix it
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Old 01-02-2021, 05:10 PM   #13
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Quote:
Originally Posted by Whitenukl View Post
I appreciate the feedback. It only had 11k on the clock so no mods for me yet. Previous owner put a Cobb intake on it already so that will stay in place for now. Not doing it like my last Subie...if I do mod it, It will be a simple exhaust, access port and a good tune. Def will look into the killer b and keep the T6 fresh. Thanks everyone
I would have it tuned even with just an intake. That can make them run lean. If going to drive it hard (autocross, HPDE etc) Iíd get an aftermarket oil pick up and baffled pan, cylinder 4 cooling modification, And a pro-tune.
Iíve had 2 stiís and have always gotten a pro-tune. Iíd expect the same risks they have always had if the car will be modified and driven hard. And like many others will tell you, use good oil, check it often, and change it often. Enjoy it!
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Old 01-02-2021, 06:06 PM   #14
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Quote:
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I don't have the specs in front of me but I doubt Subaru opened up the ring gaps in later EJ257s so the chances of a ring land failure under the right conditions are probably still there.
Seconded - you can break these if you piss pound them, and at least for me the failure mode was as described above.

Recently lost #4 piston in my Type RA/2019+ STI shortblock after 35k miles. I was not kind to the motor in terms of driving style, but the tune wasn't nuts and done by a reputable tuner. In the ballpark of 350 whp on E85. On teardown I found obvious signs that the second ring butted, with ringland cracks above and below the gap. Signs that that cylinder ran hotter than the others, no cooling mod and still UEL.
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Old 01-04-2021, 01:20 PM   #15
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I would have it tuned even with just an intake. That can make them run lean. If going to drive it hard (autocross, HPDE etc) Iíd get an aftermarket oil pick up and baffled pan, cylinder 4 cooling modification, And a pro-tune.
Iíve had 2 stiís and have always gotten a pro-tune. Iíd expect the same risks they have always had if the car will be modified and driven hard. And like many others will tell you, use good oil, check it often, and change it often. Enjoy it!
I only plan on doing ďspiritedĒ driving. Meaning acceleration into traffic when needed. Never redlining, no events, no clutch dumping or any of that horse****. Itís a daily and I plan on keeping it that way. I may not even mod it all and just keep it the way it is...stock other than the Cobb intake. Maybe an exhaust. With that info, would you still suggest and AP and a tune? As well as the killer b? Also can you explain the #4 cooling mod?
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Old 01-04-2021, 01:34 PM   #16
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To use any after market intake you will need a tune. Cobb has an OTS map for stage 1 w/Cobb intake. It's a starting point. But in all honesty, these cars don't need an intake other than OEM unless you're going to a largish turbo as the OEM intake design is quite efficient. Personally, I'd still get an AP and an aftermarket catted down pipe and go to stage 2. That's where you really notice the car start to come alive and have better driving characteristics. Either way no need to change the intake. If you want to use any of the OTS maps Cobb supplies then you should follow the exact parts they recommend otherwise you will adding risk of failure.

The cyl 4 cooling mod adds a small section of coolant line from the back of the engine by the starter that goes to the heater core return hose. This allows for coolant to flow out of the cyl 4 area more efficiently, reducing cyl 4 temps and improving reliability.
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Old 01-04-2021, 05:04 PM   #17
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Quote:
Originally Posted by Whitenukl View Post
I only plan on doing ***8220;spirited***8221; driving. Meaning acceleration into traffic when needed. Never redlining, no events, no clutch dumping or any of that horse****. It***8217;s a daily and I plan on keeping it that way. I may not even mod it all and just keep it the way it is...stock other than the Cobb intake. Maybe an exhaust. With that info, would you still suggest and AP and a tune? As well as the killer b? Also can you explain the #4 cooling mod?
Like others have said, stay with the OEM intake, Cobb AP and a catted DP flash to stage 2. That's all you'll need.

For better performance and may be reliability a custom tune is the best. Again I have over 140,000 trouble free miles, my car sees redline many more times then you would ever do.

These cars are fun to launch, if you have a good clutch and know how to preload the driveline.

See, I drive much harder then you ever would, I put was putting over 17,000 miles a year driving that way. I'm retired now so the miles will drop but its still my go to car for driving to VT for skiing. 2005 Legacy GT wagon 5mt with a vf52.

The chassis has over 296,000 miles. except of O2 sensors, all OEM sensors and valves still there.
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Old 01-05-2021, 10:33 AM   #18
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Like others have said, stay with the OEM intake, Cobb AP and a catted DP flash to stage 2. That's all you'll need.

For better performance and may be reliability a custom tune is the best. Again I have over 140,000 trouble free miles, my car sees redline many more times then you would ever do.

These cars are fun to launch, if you have a good clutch and know how to preload the driveline.

See, I drive much harder then you ever would, I put was putting over 17,000 miles a year driving that way. I'm retired now so the miles will drop but its still my go to car for driving to VT for skiing. 2005 Legacy GT wagon 5mt with a vf52.

The chassis has over 296,000 miles. except of O2 sensors, all OEM sensors and valves still there.
The car already came with the Cobb intake. I donít have the OEM air box at this point. I did contact Cobb yesterday and Iíll just get the AP3-sub-004 and upload the stage 1 OTS map for now. Then Iíll prob do the Down pipe and catback and do the stage 2 map at that point. Def looking into doing the killer b and the #4 cylinder cooling mod for piece of mind. Thanks for the feedback
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Old 01-07-2021, 03:11 AM   #19
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the platform is good.

specially if you leave it alone.
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Old 01-07-2021, 08:22 AM   #20
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i agree - the platform is good!

a few preventative measures can go a long way. There may be more, but this is what I typically do:

When (not if) you get a new shortblock, before assembling anything, pop out the brand new pistons and open the ring end gaps to a more forgiving spec. There is zero downside to doing this, and it goes a long way to preventing ring land damage as pointed out earlier in this thread.

Get a good tune. Stock tunes have varied over the years, and there are things to fix. One being the closed loop to open loop delay, which should be removed (may not apply to your year) which can cause your engine to run very lean under full boost for several seconds (bad). You need the right amount of fuel, and not so much advance that knock occurs. Also actively monitor if your IAM/DAM falls below 1.000 then something is wrong and you will likely catch it before any damage is done. I have an audible alert set on mine but it's been fine.

Don't use oil that is too thin, as suggested by the owner's manual lately - it can't handle the load, especially on higher hp engines.

For some of the earlier engines, remove the banjo bolt filters and toss them out. These minuscule filters will clog, starve the turbo of oil, turbo bearing dies and sends glitter of death through engine, engine dies, then you're looking at buying a new turbo/shortblock/etc. Cycle of EJ life.

There are other things (oil pickups, keeping valve clearances in spec, etc) that can also help prolong these engines, but the big ones are above. Hope this helps.
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Old 01-08-2021, 03:02 PM   #21
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First question first: what's the best gas available to the OP in terms of AKI / octane level?
If it's anything less than 93 AKI gas, then the OP needs to think long and hard about getting anything with an EJ257 under the hood.
If the OP is planning to run ethanol blends with a flex fuel tune, or water/meth injection, to get well above 93 AKI, then, by all means, go right ahead with the EJ. That's my 2 cents.
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Old 01-08-2021, 03:12 PM   #22
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Originally Posted by neg_matnik View Post
First question first: what's the best gas available to the OP in terms of AKI / octane level?
If it's anything less than 93 AKI gas, then the OP needs to think long and hard about getting anything with an EJ257 under the hood.
If the OP is planning to run ethanol blends with a flex fuel tune, or water/meth injection, to get well above 93 AKI, then, by all means, go right ahead with the EJ. That's my 2 cents.
Not sure in terms of aki . I just know I run 93octane and thats it. Not planning on running anything else. Just got the AP and plan on doing the stage 1 OTS for now because I learned from Cobb that without the stock air box...I cant go stage 2.

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Old 01-08-2021, 03:42 PM   #23
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Not sure in terms of aki . I just know I run 93octane and thats it. Not planning on running anything else. Just got the AP and plan on doing the stage 1 OTS for now because I learned from Cobb that without the stock air box...I cant go stage 2.
If you have 93 at the pump, you're good to go.
Check your oil level regularly (I do it every time I stop to fill up) and enjoy your ride.
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Old 01-08-2021, 04:48 PM   #24
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Even on 91 these can have very reliable tunes. It's in the tuner not pushing them too close to knock threshold. Or the client not pushing the tuner to take it to the edge. People play a bigger role in the reliability of any car than simply thinking in terms of the quality of the fuel. You can tune one of these for 87 if you want, you're just going to lose a lot of power in the process.
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Old 01-08-2021, 11:25 PM   #25
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Originally Posted by neg_matnik View Post
If you have 93 at the pump, you're good to go.
I wish I could get 93 around here. Premium is 91 here... (we are at elevation - 5500-6000ft depending on where you are, so they rationalize it that way.)
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