[AnthonyLam]

My 2005 Forester xt is coming up on 180k miles so I think the engine life is coming to an end sooner than later. My knowledge of engine rebuilds are very little to none so please bear with me but I’d appreciate all the help I can get. How did you guys decide to do your rebuild and what were some of the end results?

I thought if I’m going to rebuild, I could go for some bigger power with daily drivability in the IAG Stage 1 EJ25 Subaru short block. It comes with case halves, pistons, connection rods, rod/main bearings, crankshaft & case/main bolts with the option of hardware & seals.
My second idea was being kinda conservative and going with the OEM sti short block. Includes crankshaft, bearings, rods, pistons, and main seals.
Would I need to upgrade my transmission, fuel system or turbo too or am I good with just the new short block?
When the rebuild is done, I do plan on getting a custom dyno tune from a local shop.

 

[AnthonyLam]

Forgot to mention that it’s a 5 speed mt.

 

[northman]

The big decision is whether to spend more $ on the engine than the car is probably worth. I did, because I decided I couldn't buy something else I liked better for that amount of money, so you have to like the car and be prepared to keep it for a while.

If you are thinking about more power, the choice of turbo will dictate how far down the rabbit hole you need to go. Best bang for the buck would be VF turbo, STI intercooler and various suppporting mods, for about 280-300 whp. This can be a reliable daily driver, forged pistons not absolutely needed, but would be a good idea if doing a fresh build.

If you want to go bigger, a 20G or similar turbo will put you up to about 350 whp, but will require a bit more $. Forged pistons now pretty much required, bigger injectors required, higher chance of breaking something.

Tranny will be fine at these power levels if you are not the kind of driver that trashes and bashes everything.

 

[Inactive_55959]

Agree with everything northman says. Adding a few points.

- getting an IAG block is a smart move.
- I have an 18g /8cm turbo that makes great reliable power but requires id1000 injectors, and fuel pump.
- the more power you make the more maintenence required, its not just the tranny you need to worry about.
- do yourself a favor and replace/upgrade uour stock radiator and oil pickup. Both are known to fail and kill engines. Get a killer-b oil pickup and a koyorad (or similar radiator).
- if your car still has the original catted up-pipe: replace that with a non-catted version. The catted uppipe is known to disintegrate and send hot metal into your turbo, destroying it, which can then send chunks of turbo into your shortblock, destroying that.
- if you’re gonna upgrade your turbo you’re probably going to want a turboback exhaust.
- talk to your tuner before you order all the parts for the build. The more familiar the tuner is with everything the better it will all work together once tuned.
- I love the 5mt it is light and has great ratios. That said: i have busted gears twice. If I ever have to service it again I will get a 6mt for the durability: and bemoan the changed ratios and added weight.

 

[montanasuby]

A lot of time taking a new oem short block and adding forged pistons to it while new is the way to go, especially if you add a huge turbo. Now is also the time to upgrade turbo and change all the rubber hose on the motor. I’d also think about replacing the avcs hard lines as they can have oil deposits or coking that you can’t see. Replace the turbo inlet line as well. You don’t need to upgrade the fuel system unless you have big plans but I did send my injectors to a company to have them cleaned and tested.

Replace clutch pilot bearing and have flywheel resurfaced and also if you haven’t done your fuel lines under intake manifold now is the time. Use only genuine Subaru oem fuel line or it will leak and you’ll have to do the job twice, this happened to me.

I used a new oem short block with standard pistons and added a vf 48 and supporting mods. I also did the TGV delete and used an sti oil pan, baffle and killer bee Pickup.

The expenses can eclipse 5 grand very fast.

I’d stick to the standard block and keep the power goals realistic unless this is a fun car and you have deep pockets. People like joe at asf machine in grand junction Colorado can do the piston swap and advise you. Also don’t forget the heads, I sent mine to ASF machine fed ex and they turned out great.

Lastly a compression and or subasequent leak down test will tell you the current motors health. These cars can run lean under load with factory programming causing things like burned exhaust valves. A simple vacuum gauge test can also show problems if they exist and is cheaper and easier then the aforementioned tests.

Technical Articles: Engine testing with a Vacuum Gauge - at Greg's Engine & Machine

 

[frijoles]

So, im kinda there, but not really. Engine is at 190k, running smooth still.
But i am thinking myself of the short block from iag.

Not having any funding for any power from it, but my thoughts were to replace it for a reliable daily drivier. Can i just drop in the shortblock and use oem everything else? probably will be rebuilding the stock td04.


If i find money on the ground, then ill start to put on go fast parts. but with baby on the way, that wont be for a long time.

 

[northman]

So, im kinda there, but not really. Engine is at 190k, running smooth still.
But i am thinking myself of the short block from iag.

Not having any funding for any power from it, but my thoughts were to replace it for a reliable daily drivier. Can i just drop in the shortblock and use oem everything else? probably will be rebuilding the stock td04.


If i find money on the ground, then ill start to put on go fast parts. but with baby on the way, that wont be for a long time.

Why rebuild if it is running well? As far as anyone can tell, it might have another 100K in it. Have you done a compression test? If that comes back good leave it alone. Get current on your maintenance, and save your $ for important things, like diapers and preschool.

 

[Inactive_55959]

Why rebuild if it is running well? As far as anyone can tell, it might have another 100K in it. Have you done a compression test? If that comes back good leave it alone. Get current on your maintenance, and save your $ for important things, like diapers and preschool.

I tend to agree. Better to save your money and plan for the moment when you DO need replace the motor. Dropping a brand spanking new IAG shortblock into the engine bay and hooking it up to a bunch of aging components wont do much for your ride, and may decrease the longevity of the shiny new shortblock.

 

[frijoles]

@northman i suppose the reason why i am thinking about it, is in event that the engine decides to pop, i have the plan in order, rather than plan when things go wrong.

Im sure ill be able to run the current engine to 250-300k at least. Im pretty modest with the car when i drive. do my own maintenance n such.

i guess im just a planner, and i think id want to have a savings fund made separate for it.


@The Tinman Rides Again kinda things i wana know things since running aging components would accelerate the new shortblock's life. what should and shouldnt i use?


thanks for the responses, and sorry for hijacking.

 

[northman]

[/MENTION] kinda things i wana know things since running aging components would accelerate the new shortblock's life. what should and shouldnt i use?

You want to do the entire engine the right way, which is more than just swapping the shortblock. The heads will need to be freshened up. Any hoses that show signs of getting brittle should be replaced. The turbo inlet may fall into that category. The radiator is a weak point at mileage above 80K. Good idea to replace the MAF sensor on a build that is beyond 100K. The turbo may need rebuilding or replacing. Injectors rebuilt or upgraded. A new fuel pump is a good idea, also a water pump. New timing belt. New clutch. The oil pickup is a weak point, replace with a better one. I'd replace the oil cooler as well. Probably more stuff I'm not thinking of. Ends up being a bigger job than most would think. Will you need to pay labor to to pull and install the engine? Depending on local labor rates, that can add 1 or 2 thou to the butcher bill.

 

[CRJDriver10]

Hi
I am kind of in your situation also, one option is you can get a JDM motor from JDM in Orlando FL for 790.00 delivered, its a EJ20X with a average of 50000 miles on it, you use it as a long block, just swap everything over to the JDM motor and leave the exhaust avcs disconnected. This can get you around while you take your time and rebuild your motor the right way without having to rush. When your done you can always sell the EJ20X or keep it as a spare. If your mechanically inclined you can do the swap yourself, youtube Subaru Mike, watch his videos.