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SurlyOldManMN 02-06-2013 09:15 PM

(First?) 2010 LGT Engine Failure - Hopefully a build documentation thread.
<Sappy Stuff>
Hi folks, as many of you are aware Sunday, 2/3/13 I received word that cylinder #2 has unacceptably low compression indicative of a ring or piston failure. After some consideration and a night's sleep, I decided to park the car indefinitely. I have already wiped out my car budget for the foreseeable future with an E85 conversion and several surprise repairs over the last several months (2nd new clutch after 16k of relatively gentle use on an HDSS, blew a strut, damaged rim/tire, etc).

I initially posted about the failure and decision to let it sit in the "What did you do to your 5th Gen Today??" thread. It was a decision based on numbers. I could explain what happened next but I think it's best if you read for yourself (If your page settings are different, start at post #162):

The short version is Jase2010LGT offered to rebuild my engine at cost, followed immediately by an awe-inspiring, attitude-shifting, generosity-equivilent of a steel toed kick to the face. I was not expecting, prepared or frankly able to make sense of the outpouring of support offered by our members. In case day one support didn't screw with me hard enough, Jase followed it up by setting up a paypal account and thread to provide an organized support effort (found here if that interests you).

What our community has really given me is a path back to my attitude and perspective 15-20 years ago. Back when I was convinced people were basically good and maybe we have a chance at avoiding annihilating ourselves in the near future. Thank you.

The very, very least I can do in return for the bizarre, inexplicable peace I feel right now (which ought to be impossible) is attempt a solid documentation thread.
</Sappy Stuff>

First off, I want to ensure I'm setting realistic expectations:

I don't know what the timeline is as numbers are still numbers, and they don't look good. I plan to update this thread aggressively as updates become available. Work will be completed by NF Performance when the time comes. As alluded to above, I am distrustful, cynical and generally wary of people in general (or was, anyway, now I'm just confused). NF Performance has earned my respect and trust with consistently frank, honest advice and hard work. Their deep knowledge, proven experience and unparalleled support of the local Minnesota Subaru community was already serving as an inspirition before this situation came to pass. The fact that they can build a 9 second Subaru and run it down the track more than once doesn't hurt either... ;)

As things move forward, I will detail purchased parts, dates, install experiences, etc.

I am reserving the first few posts to organize information for ease of maintenance and navigation. This is what I'm thinking, it is subject to change:

Post 2: The starting point. Current modifications and any insight that I think may possibly be useful.
Post 3: Symptoms and Diagnostics. Also lessons learned/anything I think needs to be called out for people doing research in the future.
Post 4: NF Performance recommended rescue build list (and actual list if there is a discrepency for some reason). I'll try my best to document reasons for all the recommendations, and possible other paths that are not as applicable given my conservative goals.
Posts 5+: (Hopefully photo) Build documentation.

I was hoping to have the detailed build list ready to go when I made this post, but I'm just not there yet. To that end... I could really use a part number for an OEM HG set. My google-fu is failing me. I'll get it from the dealer tomorrow otherwise. Rest assured I will be fleshing this thread out as soon as I can.

SurlyOldManMN 02-06-2013 09:15 PM

Reserved 1

SurlyOldManMN 02-06-2013 09:16 PM

Reserved 2

SurlyOldManMN 02-06-2013 09:16 PM

Reserved 3

SurlyOldManMN 02-06-2013 09:16 PM

The Build List (Recommendations Courtesy of Nuke from NF Performance)

My overall power goals for the life of the car are modest. Perhaps 400 whp many years from now when I can afford to treat the LGT as a project car and reliability is no longer a concern. For the foreseeable future, I don't see pushing her beyond 350whp. Even that is a ways out as I can't afford to upgrade induction components and my tolerance for premature failure is roughly zero.

For this build, power goals will be at or very, very near what they were before things went south: 26x whp/33x wtq. All parts recommendations are assuming these relatively modest power goals.

On to the list...

Product name/number: JE 296348
Vital stats:
Bore: 99.75 bore
Compression: 8.5:1 compression
Weight: 405 grams
This represents a .25 oversize bore. The very modest bore is recommended to repair possible damage. Final compression calculated to roughly 9.2-9.3. In theory more power can be made with higher compression pistons with less boost, off-boost performance is also improved. The trade off for those performance benefits is safety. I'm digging the whole "safety" thing and I am quite content with how the car behaves at low RPM or off boost as it is.
Honorable mention for piston selection was Manley 612002C-4:

Product name/number: Manley 15024-4
Vital stats:
Center-to-Center: 5.137"
Big End Bore: 2.165"
Big End Width: .840"
Pin Diameter: .905" (23mm)
Pin Bore: .9063"
Weight: 560 grams
There are Manley's new "H-Tuff Series" specifically designed for higher boost applications. Nuke has heard fantastic things about these from early adopters. I beam rods are not necessary given my modest power goals. Were I go to go much bigger, the 100% premium of I beam over H beam would have been a worth while investment.

Product name/number: ACL 4B8296H-STD & 5M8309H-STD
Vital stats:
All sizes standard.
Bearing/Thrustwasher/Pin set: R94125
Excellent reliability reputation. No need for fancy-pants bearings as I'm not going with a novel crank setup.

Head Studs:
Product name/number: ARP 260-4701
Url: 260-4701
Vital stats:
ummmm... they're head studs
Same as the bearings. Good reliability reputation, no need for anything crazy. Reusing stock studs is risky at best.
Product name/number: OEM 10105AB280

Keeping it stock pending unexpected damage

**Post not yet reviewed by NF Performance. Disclaimer will be removed once that is completed**

Austin2334 02-06-2013 10:30 PM

I'll be looking forward to this thread. Hope this is a positive turning point in your car and sleep;)

Fischbach31 02-06-2013 10:46 PM

Good luck in the future!! Hope all goes well!

Austin2334 02-06-2013 10:49 PM

Also, you requested the head gasket OEM part number. It looks like it is 11044aa770. Hope that helps

SurlyOldManMN 02-06-2013 10:51 PM

I'm trying to find the set as opposed to the individual gaskets. There is a bunch of stuff I assume I'm going to need.

bigjweb 02-06-2013 10:57 PM


Originally Posted by surlyoldmanmn (Post 4282309)
i could really use a part number for an oem hg set.

11044AA770 head gasket
10105AB280 complete kit

Here's a good site for finding oem parts. Doesn't list #'s like opposed forces, but it's all updated and you can search with a part#

Austin2334 02-06-2013 10:59 PM

Oh like the master set. Checks his site out. It shows the options. I'm not sure what the GT would work under. Newer WRX maybe. Not sure about that one.

From what I got from OpposedForces site. The gasket kit it is saying is the ab200 one. I can send you that link too if you want.

bigjweb 02-06-2013 11:10 PM


Originally Posted by Austin2334 (Post 4282408)
Oh like the master set. Checks his site out. It shows the options. I'm not sure what the GT would work under. Newer WRX maybe. Not sure about that one.

From what I got from OpposedForces site. The gasket kit it is saying is the ab200 one. I can send you that link too if you want.

AB200 is for 08-12 sti and 09 spec b
Overhall gasket kit for a 2010 LGT is 10105AB280

TheOneDoubleN 02-06-2013 11:17 PM

Sub'ed for awesomeness. Kind of wish I kept my total'ed one, the engine was perfectly good, could of just popped that one in.

Brainchild Customs 02-07-2013 12:15 AM

If you need to get OEM parts, send me a PM. I may be able to get them at close to wholesale through my guys out here in MD.

CL21376 02-07-2013 04:55 AM

Subscribed. Good luck getting your car back on the road.

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