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Blown HG?


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I'll say that's your problem.

 

Make sure you install ARP head studs...

 

Have you read my click here link for things to do while the engines out ? Also ready MrTris, shopping list.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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You didn't happen to do this while attempting to find the limits of the "traction control", did you?

 

Meanwhile, you need a rebuild. There's no "little as possible" here -- It's thousands of dollars done right, or you might as well just walk away. See the Shopping List.

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Wouldnt just replacing the head gasket solve the problem being that the issue hasnt evolved to trashing the rest of the motor yet?

 

How many miles on the motor? If more than 100k, do new shortblock.

 

Either way, you'll need at least the gasket kit, plus the ARP head studs.

 

Here, since you'll want to learn this stuff, it's important:

 

From here: http://www.thomasnet.com/articles/hardware/head-stud-bolts

 

Torque Efficiency

 

During engine assembly or maintenance, a bolt must be installed by torqueing it into place. Due to the head bolt’s design, it has to be rotated into its slot in order to engage the threads and secure it into place. This process creates both twisting force and a vertical clamping force, which means that when the cylinders within the engine’s combustion chamber begin accumulating load, the bolt will both stretch and twist. Because the bolt has to react to two different forces simultaneously, its capacity to secure the head is slightly reduced and it forms a less reliable seal in high-powered engines.

 

By contrast, a head stud can be tightened into place without any direct clamping force applied through the tightening. A stud can be threaded into a slot up to “finger tightness,” or the degree to which it would be tightened by hand. Afterward, the cylinder head is installed and a nut is torqued into place against the stud. The nut torque provides the clamping force, rather than the torque of the fastener itself, and the rotational force is avoided entirely. Because the stud is torqued from a relaxed state, the pressure from the nut will make it stretch only along the vertical axis without a concurrent twisting load. The result is a more evenly distributed and accurate torque load compared to that of the head bolt. This ultimately translates into higher reliability and a lower chance of head gasket failure.

 

Put simply, in most applications where a nut/bolt would be used, a stud is superior.

 

In this particular instance, installing ARP head studs is infinitesimally easier than the sequence required for correct (read: Per FSM) OEM head bolt installation.

 

Speaking of, I assume you'll be doing this yourself, per the "spend least amount possible" statement, so, you'll need a copy of the FSM, which can be found here.

 

http://jdmfsm.info/Auto/Japan/Subaru/Legacy%20Outback/2005/

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Any idea in hours, for labor costs?

 

You'd have to check something like AllData for that kind of info. But again, it should take about 2-4 hours to pull the engine, and then however-long-it-takes to send the heads out for service, plus ARP head studs ($200), plus labor, and whatever parts break during the process.

 

I stand by my estimate of $2500.

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You've been running around for a few months clutching at straws, hoping against the odds that it's something else, anything else, than a head gasket. In the meantime, your head and block have been getting progressively more distorted due to localized overheating. I did the same thing, for the same reasons, and ended up with a cracked head to show for it (though admittedly I'm running a bigger turbo and more power than you).

Don't try just skimming the heads and hoping you get away with that and the stock bolts. Chances are you will pop the new gaskets in short order and you'll spend the same money again putting it right. Your shop has to check the block halves for distortion as well and machine them flat if they're aren't to spec. I'd do that anyway to be sure. That means the shortblock is coming apart, which is more labor. You may find it more worthwhile to install a brand new factory shortblock at this point.

 

As Max suggested, go straight to head studs to be sure the gaskets get enough clamping force on them. Yes, the OEM stuff should in theory be enough but if you search around there are plenty of people who blew HGs even on completely stock setups. The stud kit is really good insurance for a few hundred bucks. So are the factory gaskets vs. pattern stuff from unknown suppliers.

Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs.
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