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2012 STi, "Natasha"

GR Sedan: 
78K views 408 replies 24 participants last post by  Leemanfor 
#1 · (Edited)

The day I brought her home. February 6th, 2015.

Parts List:
OEM Engine - Piston ringland failure on cylinder 4 at 53,212 miles on 11-20-2015. Install date 04/2012

Built Engine #1 - Piston ring failure on #2 and #4 at 29,334 miles on 04-03-2020. Install date 01-04-2016
  • Manley Platinum Forged Pistons 99.5
  • Eagle Forged H-beam rods
  • OEM 2012 STi nitrided crank
  • ARP 2000 Headstuds
  • King Rod Bearings
  • King Main bearings
  • Killer-B oil pickup
  • Killer-B baffled oil pan

Built Engine #2 - install date 05/28/20
  • BuiltEJ/Emerald Coast Motorsports closed deck case halves bored to 99.75mm, align honed using torque plates
  • JE 99.75mm Ultra series 8.5:1 forged
  • Manley H-tuff Rods
  • OEM 2019+ STi nitrided crank
  • ARP 625+ headstuds
  • King XPG "Pmax black" rod bearings
  • King XPG "Pmax black" main bearings
  • Killer-B oil pickup
  • Killer-B oil baffle
  • Killer-B oil pan

Performance: Updated 12/20/21
  • BNM Performance Fab Rotated Turbo kit
  • Borg Warner EFR 7163
    • SX-E Compressor Housing
    • 0.85 AR V-band Turbine Housing
  • Mac 4 port EBCS
  • Magnaflow Catback
  • ETS Rotated Turbo FMIC
  • Tial 50mm BOV
  • Comp MPC Organic Clutch
  • ID1300 Injectors
  • Fuel Lab 6AN Fuel filter
  • Radium TGV housings
  • Radium AOS
  • Radium Fuel rails w/ 6AN PTFE lines routed Serial.
  • Radium Fuel Pulse Dampeners
  • Radium Fuel Pressure Regulator
  • Radium Surge tank
  • Tial 44mm EWG
  • Walbro 450 Fuel Pump
  • Custom 3.5" intake for rotated setup
  • Aaron's Subaru Electronics Flex Fuel

Exterior:
  • Enkei TS-10 18x8.5 +53 in Gold
  • BFGoodrich Sport Comp 2 245/45/R18
  • Red powder coated brembos

Suspension/Steering:
  • 2015+ STi steering rack
  • Group N STi Pitch Stop
  • Group N STi Engine Mounts
  • Group N STi Transmission Mounts

Interior:
  • AEM X-line Wideband
  • Defi Red Racer oil pressure gauge
  • Defi Red Racer oil temp gauge
  • Cobb V3 Accessport
  • 3 pod A-Pillar

I am a DevOps Engineer for a Semi-conductor company in Longmont, CO. Back in 2004 when I was 17 I seen my first STI and heard that famous Subie rumble. I vowed that one day I would own one of those cars. That day finally came on February 6th 2015. I purchased a 2012 STi in Satin White Pearl with 39k miles on it for $28,000 from a Chevrolet Dealership.

I always liked the GR Sedan's and always wanted a white one. The car was Stock minus an SPT catback, RallyArmor Mudflaps and Motegi MR-118 17in wheels wrapped in Michelin Alpin winter tires.

I enjoyed the car for about 4 months stock, and then the mod bug started to itch. I went "stage 1" with a Grimmspeed CAI and OS Tune from Torqued Performance.

Then in July 2015 I purchased a CNT Catless downpipe, Grimmspeed EBCS and an V3 Cobb Accessport and went "Stage 2".

In October of 2015 I noticed I was having some issues with the car. It was bogging down a bit on power and my Accessport was not happy.


I decided to do a compression test towards the end of November...


At first I was disappointed and my wife wanted me to take it into Subaru and have them replace the short block. I didn't like that idea, because I modded it and it wasn't Subaru's fault the motor failed. So I decided to build the motor myself, because I had always wanted to do so.


I was originally going to re-use my OEM case halves, getting them honed and then using Manley drop in pistons. However, a piston install error changed that quickly.


Somehow the ring popped out and gouged the cylinder walls. So I went and bought new Case halves and got the shortblock assembled.


After it was all said and done. I really should have just purchased a shortblock from IAG. My wife was complaining to me about how much it cost, so I tried to do the "cheaper" route to appease her and in the end, I spent the same amount of money on it. Too late for that now. At least I can say I built it myself.
 

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#111 ·
Re: 2012 STi, "Natasha"

well I ordered some parts from silicone intakes to fab up the piping needed to connect the Intercooler pipes. but i was not happy with the fitment. the mishimoto FMIC kit is a clockwise rotation so the turbo hot side piping has to go under the throttle body. that wasn't a huge issue, but was an issue was the fact the cold side piping made it near impossible to fit an intake correctly.

so i decided to sell the kit, and ordered the ETS rotated FMIC kit.

also cleaned up and created my Coolant/oil lines this weekend and now just waiting on the intercooler kit.

 
#116 ·
Re: 2012 STi, "Natasha"

Been a few days since i actually updated tis with pics.

but i ordered the FMIC from a guy on Facebook who had a rotated kit with ETS. he had it annodized fucking purple which I disliked. My buddy eric is a chemist so he and I stripped the annodizing off the intercooler but it was apparent it still needed to be painted.

 
#117 ·
Re: 2012 STi, "Natasha"

awhile back I swapped to Radium surge tank with Walbro 450. I didnt know that the radium surge tank didnt have a filter and that they recommend you run an aftermarket one before the injectors to keep everything kosher. good thing I didnt clog an injector...

Decided to buy a fuellab filter with fiberglass element

 
#125 ·
Re: 2012 STi, "Natasha"

Been a busy weekend! heres how she looks right now all finished.



Finished up the turbo install. Couple of fuel leaks and she fired up and sounded so good. Then the oil return line failed and dumped oil on the ground. Damnit jim. I guess you can't clamp braided lines with hose clamps. luckily for me, Jason had a 10AN to hose barb so i can install the new return.

I also noticed I hooked my coolant feed/return up on the EFR wrong. Need to swap those but i have to take them off anyway to pull the return.

meanwhile, its supposed to snow this weekend. :censored::censored:
 
#126 · (Edited)
Re: 2012 STi, "Natasha"

Figure I could provide an update on this turbo... Here is a comparison of the old turbo (4th gear) on E85 in S# vs the 7163 (3rd gear) on E66 in S-mode. As ethanol content comes up, so will boost in both S and S#. Now that boost is set in S-mode, timing will be added and AFR leaned out, but we've almost got S# set... Just waiting on another log.


I think S-mode will make more power than the last setup did at all. :)




I-mode boost, which is just wastegate spring. This will be the same for E0 - 100.

 
#129 ·
Re: 2012 STi, "Natasha"

Car pulls so hard. I am in love with this turbo. Seriously, and we aren't even done tuning.

On a side note, the EFR does not like the Tial BOV. so im switching back to the provided BPV.
That seems like a great plot. Especially for the lower cost pressures. 25 psi and nearly 480whp is great.

How is transient response? When does the turbo come on to boost?


Sent from my SM-G955U using Tapatalk
 
#130 ·
Re: 2012 STi, "Natasha"

I imagine the transient response is just as good as my 6758. If it weren't for the FMIC piping and stock manifold, I'd say it'd spool a lot like mine as well. The 24 PSI graph is a little soft as it spools towards the top. It should improve on the last map I sent him. :)

I'll have him do a 4th gear pull soon and see how that affects the boost threshold. Once the ethanol content comes up, it should be around 26 PSI at our altitude.
 
#135 ·
Re: 2012 STi, "Natasha"

Someone finally got me some more logs... :) First 4th gear pull really picks up. The next map, which he'll try on the way to work tomorrow, had me adjusting per gear boost tables to get the spool on target immediately. This is still on E66 and looking forward to E85+!

 
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