2.5 vs 2.0
Hello all
I am a new member seeking info.
Used to own the Bugeye 2000 WRX and loved it.
I am now looking at buying a 2012-2013 2.5 litre WRX.
Have heard issues with Piston problems regarding Ringland which
can cause heaps of damage.
Can any owners put me on the straight and narrow.
Should i be concerned about buying one of these great cards or not.
Thanks from Wayne in Adelaide.
I am a new member seeking info.
Used to own the Bugeye 2000 WRX and loved it.
I am now looking at buying a 2012-2013 2.5 litre WRX.
Have heard issues with Piston problems regarding Ringland which
can cause heaps of damage.
Can any owners put me on the straight and narrow.
Should i be concerned about buying one of these great cards or not.
Thanks from Wayne in Adelaide.
They can be problematic if not serviced properly or modded by someone who does not know what they are doing. At the end of they day, the 2.5 is a decent motor if treated with respect.
Get one with a known service history and no mods and you'll more likely to have no issues.
There are a lot of misconceptions out there but didn't put me off getting a 2016 STi.
Get one with a known service history and no mods and you'll more likely to have no issues.
There are a lot of misconceptions out there but didn't put me off getting a 2016 STi.
You're a braver man than me.Yep the world sure is full of misconceptions but the Subaru 2.5L engine ain't one of em!

Fill your boots Wayno...
https://www.scoobynet.com/scoobynet-...-failures.html
As what ngbz said. Great cars when they are serviced properly. some 2.5's are bad some are good. Aslong as you treat them with respect you should be alright. Sti 2.5's seem to go more than the wrx's, but I think that's because the wrx piston compression is different to the sti.
the 2.5 is a great engine when built right, problem is they weren't. In standard form they have a habbit of breaking ring lands and blowing headgaskets (make rovers look reliable).
It's pure pot luck whether they go or not, i've seen high mileage cars treated like crap still going strong and i've seen low milage well looked after cars fail under 10k miles, it's just how lucky/unlucky you are rather than how well looked after or anything else.
Once they have a bit of love, decent rods, pistons and head studs they will be very reliable even at 450bhp and make a cracking road engine. Even to the point of i have had a forged, closed deck one put in my type R with the goal of running it between 500 and 550
It's pure pot luck whether they go or not, i've seen high mileage cars treated like crap still going strong and i've seen low milage well looked after cars fail under 10k miles, it's just how lucky/unlucky you are rather than how well looked after or anything else.
Once they have a bit of love, decent rods, pistons and head studs they will be very reliable even at 450bhp and make a cracking road engine. Even to the point of i have had a forged, closed deck one put in my type R with the goal of running it between 500 and 550
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The torque from a built 2.5 is endless. I wouldn't trust a standard one, but if you can find a car with a properly forged 2.5 you won't be sorry.

But, and this has to be taken into account, how easy will it be to sell when the time comes? When running well the 2.5 is an awesome engine
what would you suggest to do to help prevent having to have a engine rebuild at some point? That isn't going to soar the earth now
seriously just service regularly and enjoy the car, some 2.5's have gone over 100k miles with no problems, however, you must be prepared for the worst.
As above. It's pure pot luck. Seen some abused and never go, seen some babied and go in very short order.
Bear in mind it's cheaper to sort it rather than fix it, so could always budget for a rebuild when you buy and have it done straight away.
Bear in mind it's cheaper to sort it rather than fix it, so could always budget for a rebuild when you buy and have it done straight away.
Won't be able to stay of the boost lol like it to much, I will just drive it till or if it does go bang not point worrying now I guess a put a big deposit down so I can't back out now otherwise I will lose it,
cheers for the advice guys
cheers for the advice guys
Last edited by Gav81; Mar 31, 2017 at 05:37 AM.
not all 2.5 break , luck of the draw plus good servicing and sensible warm up , of heads go do a full rebuild as bottom end very likely to go with in a year or so , on the 2 litre the bottom ends tend not to fail as much after a rebuild
Most 2.0's are getting on in miles now, so since your 75% of the way there may as well do them.
Wishful thinking is that 2.5 failures are due to poor mods or servicing by others. Until it happens to you.
Strikes me that the EJ257 was a cheaply adapted design from a normally aspirated engine, forced on them for emissions reasons for their target output.
A lot of failures in the aftermarket that were supposed to have been done properly never reached the public domain.
Strikes me that the EJ257 was a cheaply adapted design from a normally aspirated engine, forced on them for emissions reasons for their target output.
A lot of failures in the aftermarket that were supposed to have been done properly never reached the public domain.
Last edited by john banks; Apr 1, 2017 at 02:05 PM.
Wishful thinking is that 2.5 failures are due to poor mods or servicing by others. Until it happens to you.
Strikes me that the EJ257 was a cheaply adapted design from a normally aspirated engine, forced on them for emissions reasons for their target output.
A lot of failures in the aftermarket that were supposed to have been done properly never reached the public domain.
Strikes me that the EJ257 was a cheaply adapted design from a normally aspirated engine, forced on them for emissions reasons for their target output.
A lot of failures in the aftermarket that were supposed to have been done properly never reached the public domain.
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From: Api 500+bhp MD321T @91dB Probably SN's longest owner of an Impreza Turbo
I had a 2.5 with a MD321T, it was stupidly fast but ultimately unreliable unless carefully mapped. It failed the last time whilst it went to a third party mapper up in Carnforth-he paid me out !
My engine builder was also steering away from 2.5 blocks for big power and recommending 2 litre (ideally CDB) with a stroker kit to make 2.1
Do people still modify Subaru anymore? Mine went years ago and wont buy another, I just see the odd older and older rust buckets around these days
My engine builder was also steering away from 2.5 blocks for big power and recommending 2 litre (ideally CDB) with a stroker kit to make 2.1
Do people still modify Subaru anymore? Mine went years ago and wont buy another, I just see the odd older and older rust buckets around these days
Last edited by andy97; Apr 4, 2017 at 07:21 AM.
I had a 2.5 with a MD321T, it was stupidly fast but ultimately unreliable unless carefully mapped. It failed the last time whilst it went to a third party mapper up in Carnforth-he paid me out !
My engine builder was also steering away from 2.5 blocks for big power and recommending 2 litre (ideally CDB) with a stroker kit to make 2.1
Do people still modify Subaru anymore? Mine went years ago and wont buy another, I just see the odd older and older rust buckets around these days
My engine builder was also steering away from 2.5 blocks for big power and recommending 2 litre (ideally CDB) with a stroker kit to make 2.1
Do people still modify Subaru anymore? Mine went years ago and wont buy another, I just see the odd older and older rust buckets around these days
a 2.5 with a sensible map about 1.3 bar boost and forged is a good lump , plus slow warm up and regular service , the torque is much greater than the 2 litre , and cars are a lot more driveable , use arp or like head bolts or the hg issue can return more easily , 2 litres are stronger but lack the torque , a 2 litre stroked engine could be best of both worlds but i don't know if there are downsides of stroking them ?









