Which EJ Engine is the best over all choice?

[WhirlpoolBrewer]

I've done a bit of research on the EJ series engines and have learned quite a bit, mostly from wikipedia. Everything seemed to point to this being a pretty good peice of technology, specially around 2008 when it won some award for best 2.5 liter engine. Then I stumbled upon some article talking about how the 2.5 liter engine is arguable the worst engine out there, because of a poorly designed head gasket. I've read some reports claiming that it has been fixed, others saying that to this day it hasn't been fixed. I even read one claim saying that 90% of these head gaskets will go bad before it reaches 100,000 miles.

I don't beleive everything I read on the internet, so I thought I'd ask you guys. When I go to pick out a donor car, should I avoid certain models? For those curious about the models in question, I've read reports of this happening on the years from 1998 - 2005. Thanks in advance for your insight.

[ddorrer]

Perhaps the Subaru 2.0L Turbo Diesel could be an an option towards the World Car goal. Most countries already support diesel technology. Improved mileage with improved torque and performance should be looked at.

[Sergio]

I would wait until FFR announces the "official" donor(s) for this vehicle.

However, I have a 1999 Legacy GT 2.5 with the EJ25DE engine and the headgaskets went bad at around 99K, I (myself) replaced them, and in the process of dissasembly/re-assembly I gained a lot of admiration and information for this little engine. I am truly amazed at how easy it is, I was affraid of it at the beginning but now I love it. even have a spare EJ25DE waiting to replace the original still in the car. I believe all EJ series engines are very similar, with many parts interchanging.

[sonicrex]

Too bad we don't get the diesel over here.
I had a long thing written up for you Brewer but too keep it simple all wrx's from 02-05 are essentially the same. 06+ they went 2.5 liter. A bit more power and off boost torque.
STi's 04 and up are pretty much the same as well. Some slight turbo changes through some of the years but they are about equal. STi's have a semi closed deck/AVCS vs the open deck of the wrx.
I don't think you can go wrong with any wrx/sti engine in an 1800lb car.
I haven't heard of head gasket problems since the 98 2.5rs.

[keys2heaven]

Good question. I've been looking at what would be the best option: crate engine, donor engine, roll your own. Just don't know enough about these to make decision at this point.

I agree that we need to learn more about the donor vehicle specs.

[PhyrraM]

The ones known for the headgasket problems (and piston slapping too) were the '96-'99 2.5 liter DOHC normally aspirated motors. I wouldn't let that stop me from using one if it fit my performance/budget criteria.

The slapping issue is a cold, cosmetic issue. It doesn't effect performance or longevity, but can be annoying to listen to on a cold motor.

There isn't a single '90+ EJ series motor that I would avoid. If your budget and goals say a 120HP motor will do the job, an early Legacy or Impreza (2.2 or 1.8) is reliable as anything, cheap too. There are 2.2 SOHC turbos @160HP, 2.5 DOHC and SOHC @160-170HP normally aspirated, 2.0 Turbos @ 230HP, 2.5 turbos from 230-300HP. That list doesn't include the multitude of imported motors we never got in the USA from the factory.

Cliffs notes.....

Change the head gaskets before install on some motors and there will be no worries.
Choices range from 120HP @ $300 to 300HP @ $3500+ using factory motors.
Import motors and the aftermarket = The skys the limit.

[WhirlpoolBrewer]

Thanks for all the advise. In the past my engine preference has always been towards higher displacement engines that are naturally asperated. I've also been of the opinion that a newer design is a better design (Not ALWAYS the case, but usually). So I've really been trying to decide do I want a SOHC naturally asperated 2.5i or a DOHC turbo 2.5i, probably a crate engine from a dealership. From what you guys are saying though I suppose I shouldn't be too worried about picking up a 2.5i engine which ever one I finally decide on.

[WhirlpoolBrewer]

The ones known for the headgasket problems (and piston slapping too) were the '96-'99 2.5 liter DOHC normally aspirated motors. I wouldn't let that stop me from using one if it fit my performance/budget criteria.

The slapping issue is a cold, cosmetic issue. It doesn't effect performance or longevity, but can be annoying to listen to on a cold motor.

There isn't a single '90+ EJ series motor that I would avoid. If your budget and goals say a 120HP motor will do the job, an early Legacy or Impreza (2.2 or 1.8) is reliable as anything, cheap too. There are 2.2 SOHC turbos @160HP, 2.5 DOHC and SOHC @160-170HP normally aspirated, 2.0 Turbos @ 230HP, 2.5 turbos from 230-300HP. That list doesn't include the multitude of imported motors we never got in the USA from the factory.

Cliffs notes.....

Change the head gaskets before install on some motors and there will be no worries.
Choices range from 120HP @ $300 to 300HP @ $3500+ using factory motors.
Import motors and the aftermarket + The skys the limit.

Actually I don't think I came across that DOHC 2.5i Naturally asperated engine in my searches, but that sounds like the one I'm looking for. Then again I have no experience with turbo motors so maybe I'm just being a bit closed minded. I would love to hear what you guys have to say about the turbo versions.

[Sergio]

The ones known for the headgasket problems (and piston slapping too) were the '96-'99 2.5 liter DOHC normally aspirated motors. I wouldn't let that stop me from using one if it fit my performance/budget criteria.

The slapping issue is a cold, cosmetic issue. It doesn't effect performance or longevity, but can be annoying to listen to on a cold motor.

There isn't a single '90+ EJ series motor that I would avoid. If your budget and goals say a 120HP motor will do the job, an early Legacy or Impreza (2.2 or 1.8) is reliable as anything, cheap too. There are 2.2 SOHC turbos @160HP, 2.5 DOHC and SOHC @160-170HP normally aspirated, 2.0 Turbos @ 230HP, 2.5 turbos from 230-300HP. That list doesn't include the multitude of imported motors we never got in the USA from the factory.

Cliffs notes.....

Change the head gaskets before install on some motors and there will be no worries.
Choices range from 120HP @ $300 to 300HP @ $3500+ using factory motors.
Import motors and the aftermarket = The skys the limit.

Completely agree with your words.

WhirlpoolBrewer:
WRXs and STi are the ones that come turboed by the factory, while the Legacys, Outback and Foresters are not (some of the newer ones are however).
My 99 Legacy GT 2.5 is NA making 170 HP, I love that car.

[wjfawb0]

The 04, 05 and I believe 06 USDM STi's also have sodium filled exhaust valves. The lower compression (I believe 8.5:1) STi motors might be better tuned for tracking, but you'll also only get 23mpg. I always get depressed when I remember that my 03 Cobra mustang got the same mileage as my two 05 STi's did on the highway. The biggest advantage of the USDM STi over the WRX was the transmission for me -- 6 speeds and much stronger than the 5 speed. 05+ STi's have a limited slip front diff also. That would be very desirable in a midengined, RWD subaru based car.

[subyrod]

Here's my experience with my 2002 WRX which has the 2.0L turbo motor, stock boost is 13.5psi, 8.0:1 compression and open desk block as mentioned above. It has 129k miles on it. It's had a Cobb Accessport tuner with Stage II map in it for at least 50k miles. Stage II is the tune you load whwen your car has an up pipe (connects exhaust manifolds to the turbo) and 3" turboback exhaust. The stage II gives it about 1.5-2psi more boost. Stage II typically gets you about 275-280hp at the flywheel from the stock 227hp (02-03 specs). That's on the stock turbo. I do have a K/n panel air filter and Samco turbo inlet hose with stock intercooler. If you do headers, bigger intercooler and turn boost up another 1-2psi, you can get 300hp at the flywheel easy. Put the STi turbo in, bigger injectors, 255 pump and with 18-20psi of boost and you're 350-375hp. That's with factory parts, more boost and a tune. What I've read is anymore than about 400hp at the fly on these engines (WRX with open deck) and you're maxed out on stock pistons/rings and rods.
My dad has an 03 WRX. He homemade an up pipe and downpipe, homemade air silencer delete, manual boost controller at about 16psi and the Cobb Stage II. He's got 198k miles. He put those parts on with less than 5k miles. It's still on the stock turbo (which he ported a bit). It ran 13.9 at Famoso dragstrip with just the exhaust and intake mods uncorked. Stock clutch too. He drives 95% highway in Cali desert.
I get 28.8 mpg average in the summer driving about 60mph on 90% highway driving. I'd expect low 30's to mid 30's in a car half the weight and better aero.

[subyrod]

As far as the best years, obviiously the STi engine and 6 speed manual trans is the best. Boost is about 16-17 psi stock and they were rated at 290-300hp/tq. It also has brembo bigger brakes and the 5x114.3 wheel bolt pattern (except 2004, that's 5x100). STi's are from 2004-2012. All STi's have the 2.5L motor and bigger turbo and intercooler.

The best WRX's performance wise are 2006-07 I think. Starting in 08, they had plastic intercoolers. The 2.5L WRXs have slightly bigger injectors too. Better brakes than 2002-05 too. Trans is the same (as far as I know).

[BrandonDrums]

You can't go wrong. Nearly any Ej will fit and do well. I bet the H6's won't have much trouble fitting in there too. The real limitation will be transmissions. Only the 5mt will really make sense.

The 6mt's are too heavy, complicated and worth too much to hack up for these cars. The gear ratios are also so close that on a light-weight car like this you'd have a tough time getting enough load on the engine to spool a turbo bigger than doorknob.

WRX guys will spend 3500+ on a good 6mt. A 5mt can be had for less than 1K and have many more drop-in front diff, gearset and conversion parts to be had.

Subaru engines though, they really are like leggos.

[subyrod]

My 2 cents is get the 2002-2005 WRX. My 2002 has about 280hp with just exhaust and a tune. My buddy at work has an 07 with 18G turbo, bigger top mount intercooler, injectors and tune with full exhaust. We raced up an onramp to about 85 and up to about 70ish, I was hangin' with him. My car cost me $8500 with about $4000 in mods (wheels/tires, STi interior, Japanese projector lights, STi scoop, full exhaust, Cobb accessport, springs/shocks, bodylip kit, shifter. His cost $20000 with springs/shocks, swaybars, bigger turbo, intercooler, injectors, exhaust and tune. In a car as light as the FFR Kamikaze (just tryin' out my name idea haha), 280hp is gonna be ridiculous. 350hp will just spin tires. Bang for buck, 2002-05 2.0L WRX is best.

[Flyinglow]

One issue that may be a problem with the 6mt is finding a company that does the reverse crown cap. Easily available for the 5mt, but have yet find one for the 6mt. This is the part that is needed for the 4wd to 2wd configuration.

[Benji]

What's the best EJ engine?

These ones of course!

[legacy_y_tu]

The head gasket issue is an old one and has been resolved many years ago. As you found this 2.5 won Engine of the year award in 2007. It was a new design in 2005.

I had a 2005 Legacy with the 2.5L DOHC turbo and it was a terrific engine and great car...I still regret selling it. If I do go forward with this build I'd use a crate motor of this engine (2005-2009) because it was so robust and strong and pretty free revving engine. I especially loved the sound to the engine, similar to a Porsche. Yes these turbo cars (except the STI) use intercoolers with plastic end tanks, but that in my opinion is a good thing because they don't get heat soaked. I swapped my stock one out for a cast aluminum larger core intercooler and switched it back to stock after only 3K miles. The damn thing got so hot I could literally cook an egg on it and turbo lag went up tremendously. The ONLY bad thing about the stock plastic endtanks was that if you ran high boost (greater than 18psi) the endtanks tended to work their way loose from the core leading to an intake leak eventually. I ran 17.5 psi boost for 80K miles with no problems on my stock intercooler, others did have problems though. If we could get the intecooler designed in a location where it wouldn't heat soak from the engine that would be a bonus so we could run these larger, one piece intercoolers.

[C.Tree]

There isn't a single '90+ EJ series motor that I would avoid. If your budget and goals say a 120HP motor will do the job, an early Legacy or Impreza (2.2 or 1.8) is reliable as anything, cheap too. There are 2.2 SOHC turbos @160HP, 2.5 DOHC and SOHC @160-170HP normally aspirated, 2.0 Turbos @ 230HP, 2.5 turbos from 230-300HP. That list doesn't include the multitude of imported motors we never got in the USA from the factory.

Cliffs notes.....

Change the head gaskets before install on some motors and there will be no worries.
Choices range from 120HP @ $300 to 300HP @ $3500+ using factory motors.
Import motors and the aftermarket = The skys the limit.

PhyrraM, What suppliers sells used EJs (imported from other countries) in the US. Thanks

[C.Tree]

Or when I buy a crate motor; do I go to the dealer or other vendor? Does Subaru have a performance parts division? Thanks

[Kasmodean]

C.Tree, you are going to need a donor car to build this kit and most likely that donor will come with an engine. I would wait until you get your donor before you decide to buy a crate motor. The engine in the car might be fine. No need to buy two engines, unless the engine you want doesn't come in a car that you can use as a donor. And if this is the case, you might want to look at the reasons for you choice of engine and if the engine in the donor can meet the requirements while speeding less money then sourcing a second motor.

[Justen]

C. Tree, look at Beji's post #16 those are probably the best motors you are going to find, but your gonna pay for it. You will be much better off getting a donor car

[audsyn]

Does Subaru have a performance parts division? Thanks

http://www.subaru.com/subaru-perform...ing/index.html but they don't sell crate STi motors.

2.0L engine assy is $5k from the dealer but no one does that, there's lots of engines available.

[Hondaslayer]

Just to put an end to it right now, Subaru does not normally sell a complete crate motor. A dealership can order one for a warranty claim on a new vehicle, but that is it. Once the very limited amount of crate motors available are gone, they are gone. You can purchase a shortblock, heads etc... all separately and assemble it yourself, however you are looking at ~ $10,000 in parts (MSRP) so yeah, just buy a wrecked car.

[Seagondollar]

A Mechanical Engineer friend of mine some years back often referred to loading his money gun to go to work on a car project or another. I would suspect you might find a deal for a grand or I searched and found JDM STI engines for about 8 grand. How big is your clip?

[Nativo]

One thing to keep in mind is that most of the best transmission gears were designed for the 2.0L and as such the rpm drop was perfect for the high revving 2.0L. Same thing with the JDM EJ207 2.0L and the JDM 6sp, for the USDM from 04-06 they took the same JDM 6sp and replaced the 5th & 6th gear to make them longer while using the USDM 2.5L torquey/low revving engine. In 2007 the introduced for the USDM a complete loger ratios 6sp tranny.

So in my opinion either use a 2006+ STI engine and tranny or a JDM 2.0L STI engine with it's tranny.


Just my $.02


Nativo

[MHCobra]

We have an '04 Forester XT with a 2.5 turbo with an auto trans. The engine power is awesome, but the AT has way to much turbo lag. Are the manuals much better or closer to no lag?

Mike

[sonicrex]

Subaru is champion when it comes to making the worst automatic transmissions out there. The M/T is much better.

[MHCobra]

Subaru is champion when it comes to making the worst automatic transmissions out there. The M/T is much better.

Good to hear.

Mike

[Nativo]

We have an '04 Forester XT with a 2.5 turbo with an auto trans. The engine power is awesome, but the AT has way to much turbo lag. Are the manuals much better or closer to no lag?

Mike

Just get a 3.0" turbo-back, a K&N panel filter and a COBB Access Port. I'll assure you you'll have a completely new car in your hands. No Porsche Cayenne can keep up and V8 Hemi is no match 0-100.


Nativo

[iamsam]

The engine design is 20-30 years old. They introduced some new tech on the way, but until just the 2012 forester they have used a design that is decades old.

[iamsam]

In 09 the WRX got 265 HP by using a modified STi turbo among other things. 08 was a joke. I really think some of the JDM 2.0 twin scroll turbo motors would be great donors. For high HP applications, getting custom built motor is a good option.

[iamsam]

The 6spd does have the LSD and better oiling though. That would be extra on top of the price of a 5mt.