2012 Subaru Impreza WRX Journal

This is a work in progress. Please excuse the spelling and grammatical errors, I’m definitely not a writer by any stretch of the imagination.

Prologue

Before I bought the Subaru I owned a practical yet fun to drive 2007 Honda Civic Si. With room for five people, a decent size trunk for groceries, and a really nice 6 speed manual mated to a high revving two liter engine, it wasn't a bad compromise.

I also had a 2006 Honda CBR-600RR motorcycle which provided me with some extra thrills. The bike was much faster than the Civic (obviously) and it was also a great way to commute since it used less fuel. And when I revved the engine out to 15,000 rpms the bike sounded like a formula 1 car.

Both of these vehicles were great when I lived in Florida. I didn't have to worry about snow and ice or long cold winters. Potholes weren't nearly as common as there are in the Northeast. And when it came to the motorcycle, the drivers in Florida were much more motorcycle conscious and had more respect for motorcyclist unlike the entitled assholes in Pennsylvania that seemed to constantly tailgate me even though I was going over the speed limit. I know that those assholes are the minority, however all it takes is one to ruin your day or life when you're on a motorcycle.

Things changed in 2010. I left Florida and moved to Pennsylvania. Not much later my son was born and that's when I decided to sell my bike. I really didn't want to, but the risk of being in an accident was much higher in Pennsylvania. While the car was still pretty fun I missed the excitement of the motorcycle. With the Civic past the 100,000 mile mark I decided to look for something that could be more fun yet still practical.

I knew what I wanted, it was a car that I had an appreciation for since the mid to late 90s when I'd see them ripping up rally stages with their iconic hood scoop and unique exhaust note. It was the Subaru Impreza WRX.

Unlike the rally cars of today, rally cars of the 90s looked like mildly modified street cars. They looked like something that the average person could obtain, yet they performed incredibly across all types of terrain and in all types of weather. These modest looks and high performance were extremely appealing to me.

The WRX version of the Impreza didn't make it to the United States until the early 2000s, nearly 10 years after the Japanese and European markets. In Florida it wouldn't be too often that I'd see a WRX. But once I moved to Pennsylvania I'd see them regularly. In fact, I would see a lot more Subarus in general in the Northeast. Of course it's not too much of a surprise considering they do so well in the snow.

By the time I was in the market for a WRX, Subaru was on their 3rd generation. It performed well, it was practical, and most importantly, it was fun to drive. I wanted the STi version, however I couldn't justify the extra cost, especially with a newborn. I shopped around for a few months and decided to go check out a used hatchback with the iconic World Rally Blue paint. As it turned out, the dealership I went to had a few WRXs available. As I was comparing them I soon discovered that the blue WRX was a base model with a cloth interior, basic radio and no real niceties. It also had over 10,000 miles which isn't much. However, for $3,000 less I could get a gray WRX that was fully loaded. And that's what I chose.

2007 Honda Civic Si
Kennedy Space Center, Florida – March 6 2009

2006 Honda CBR-600RR
Melbourne, Florida – February 28 2006

Modifications List

Audio

Sony XAV-AX5000 Digital Multimedia Receiver with Apple CarPlay
Polk Audio DXi6501 6-1/2" component speaker system - Front & Rear
JL Audio CS110RG-W3v3 Sealed PowerWedge Subwoofer
Alpine MRV-F300 4-channel Amplifier - 50 watts RMS x 4
Alpine MRV-M250 Mono Subwoofer Amplifier - 250 watts RMS x 1

Brakes

Stoptech Drilled Front Rotors

Drivetrain

ACT StreetLite Flywheel
Exedy Stage 1 Organic Clutch Kit
Kartboy Short Throw Shifter
Torque Solution Solid Billet Shifter Bushings
IAG Street Series Pitch Stop Mount
IAG Street Series Transmission Mount
GoodRidge Stainless Steel Coated Clutch Line

ECU

COBB Tuning AccessPORT V3
R/T Tuning Stage 2 Pro Tune

Engine

IAG Oil Control Baffle & Windage Tray w/ V2 SS Oil Pickup
ATI Super Damper Harmonic Balancer
STI Group N Engine Mounts

Exhaust

Killer B Motorsport 4-1 Holy Header & Up-pipe - SWAIN Coated Equal Length Header
COBB Tuning Downpipe - Catted Bellmouth
COBB Tuning Turbo Heatshield
COBB Tuning 3 inch Cat Back Exhaust
SPT Cat Back Exhaust - Removed and sold. Resonated terribly between 1.5-2k rpms.

Induction

COBB Tuning Short Ram SF Intake
COBB Tuning SF Intake Air Box
Perrin Silicone Turbo Inlet
GrimmSpeed Top Mount Intercooler
Process West Billet TGV Deletes Removed due to government regulations bullshit.

Suspension

KW V1 Coilovers
Cusco Front Pillow Ball Upper Mounts
Whiteline Rear Lower Control Arms
Perrin 25mm Front Adjustable Sway Bar
Perrin 22mm Rear Adjustable Sway Bar
Kartboy Front & Rear Endlinks

The Beginning

December 2012 - 2013

The WRX was quite the change from the Civic Si. Besides having more power, the grip during acceleration was quite impressive.

To Be Continued…

First snow drive, only three weeks after I purchased the WRX.
Green Lane Park, Pennsylvania – December 29 2012

Bring The Noise

January 28 2020

Out with the old, in with the new.

Part of the reason I was drawn to the WRX was for it’s rally heritage and it’s unique sound. When I first purchased the car I almost imediately istalled a new exhaust. Unfortunately for me, the exhaust I chose initially wasn’t what I’d expected. I ordered a SPT (Subaru Performance Tuning) exhaust. It’s a part that Subaru manufactured and it was supposed to be a mild increase in sound. However the acoustics of a hatchback are quite different from a sedan and this exhaust didn’t pair well in my opinion.

The sound inside the cabin was obnoxious. At low RPMs the exhaust had a terrible resonance that just sounded like a really loud subwoofer playing a constant 60Hz sine wave. and at mid to high RPMs the exhaust seemed even quieter than the standard OEM exhaust. I hated it and so I sold it and when back to the OEM exhaust.

For several years I’d read forums about exhausts, searching for feedback and opinions on exhausts for hatchbacks. Sadly I couldn’t find much. As most forums go there’s a lot of noise, no pun intended, and trying to sift out the useful information was just too much of a pain in the ass. I turned to YouTube to try and find some videos with well recorded sound from the cabin and was able to find a few. COBB tuning and another company I can’t remember the name of made a video that had some decently recorded sound.

My interest in purchasing an exhaust again was increasing.

To Be Continued…

Dyno Day

February 13 2020

Optimizing performance with a pro tune.

As Jermey Clarkson would say, ‘POWER!!!’

To Be Continued…

Reducing Heatsoak

March 6 2020

One upgrade that I considered but didn’t do until later in the upgrade process was replace the OEM top mount intercooler. I knew that a new intercooler was going to be necessary if I continued to increase power. And I knew the reducing heatsoak was important, but what I didn’t know was how much the driveabiliby would improve.

While sitting at a traffic light the heat from the engine rises and saturates the intercooler thus reducing it’s effectiveness. This caused power loss. Depending on the situation this could be quite noticeable.

To Be Continued…

It added some weight, but it was worth it.

Coilover Upgrade

April 19 2022

Parts fail, it’s inevitable. However, living in the Northeastern United States will likely cause parts to fail earlier that expected. Between the salt that covers the roads in the winter and the potholes that seem to be everywhere no matter what the season, vehicles of the northeast take a beating.

Well engineered and good looking

Nothing says the Northeast like road salt.

One day while performing a brake fluid flush I discovered my right-rear strut had cracked and was leaking hydraulic fluid. Obviously it was going to need to be replaced.

When I first bought the WRX I told myself that I wasn’t going to lower it since I bottomed out so many times in my lowered Civic Si since moving to Pennsylvania. However it had been 10 years since I had a lowered car and I missed the improved handling it offered.

To Be Continued…

Can’t say that I’m surprised.

A bonus weight reduction.

A little too low for the Northeastern roads.

Clutch Release Bearing Issues & 100,000 Mile Maintenance

August 2022

Enjoying working on my engine.

Was is my fault? At the time I wasn’t sure but after taking everything apart I think the answer would be yes. Lack of knowledge and inexperience are likely the causes.

In 2019 I replaced the clutch and flywheel after the clutch started slipping. This was my first time dealing with this type of problem. I had done some reading and watched several how-to videos and decided that I could take on the job. While doing the job I was very careful to recheck my work several times and double check the directions. However without being trained by someone and not having someone to ask questions too, I ended up having to make some judgement calls. One specific judgment call was the amount of grease that should be applied to the transmission quill. The instructions explicitly stated “don’t use too much grease”. Okay, that sounds good, but how much is too much and how much is too little? “Just apply a thin layer” the instructions said. So I did.

The next issues was when I was mating the transmission back to the engine. I was doing the work by myself. With the car on jack stands and laying on my back it was fairly difficult to get the engine and transmission to align properly. When trying to mate the transmission it turned out that the clutch fork ended up slipping downwards without me noticing. I only discovered this quite a bit later in the process when I was reinstalling the clutch slave cylinder. Of course I pulled the clutch fork back into what I though was it's proper position, however, I think this ultimately caused an alignment issue and prevented the release bearing from moving smoothly and prevented it from moving the full range, likely binding towards the end of the transmission quill and staying there. I assume that the clutch fork spring popped off the pivot release lever causing this issue.

Once the car was fully assembled and I took it out for the first test drive the first thing that I noticed was that the clutch engagement point was very immediate. Having never changed a clutch I wasn't sure if this was a problem or not. The replacement clutch was an aftermarket performance clutch and so I assumed that maybe this was just a design trait. Everything seemed to be operating smoothly otherwise so I just accepted this as normal and continued to drive the car.

It wasn't until late 2021 that I started getting a squeaking sound. I assumed that the bearing itself had prematurely failed and needed to be replaced. I searched the internet for people that had the same symptoms as I did and found some. Several people suggested that lack of lubrication was the problem and that spraying white lithium grease onto the bearing and the transmission quill would solve it. While this method did provide some temporary success, it didn’t solve the problem. The squeaking would come back and I'd spray grease again. I knew that it must be something else and that I'd need to pull the transmission out again.

Damage to the transmission quill.

Broken flange on the release bearing.

Damage to the pressure plate fingers.

My friends, Dave and Laura, along with their son Jaden had recently pulled the engine on Jaden's Subaru Legacy GT. They sent me some photos of the process and it looked somewhat fun. Taking a look at my mileage I saw that I was nearly at the 100,000 mile mark. The timing belt is due to be serviced at 105,000 miles so with that inspiration from my friends and the problems that I had I figured that instead of pulling the transmission again I'd have a go at pulling the engine.

I started planning for the timing belt back in March 2022. I knew that the global supply shortage and logistic issues could cause a problem so I decided to order the parts early just to be sure I would have everything in plenty of time. As it turned out, there was no issue whatsoever getting these types of parts.

Once the summer arrived and I had some time I went to work. The process of removing the engine wasn't as complicated as I thought it might be. It was tedious though. With all the different wiring harnesses and rubber hoses snaking their way around the engine to tiny hidden crevasses that couldn't be seen with the naked eye the process took quite a while. I also had to make sure I bagged and labeled all the parts as I went along.

After about a day's work I had the engine out and could finally take a look at the clutch. To my surprise I discovered that the release bearing flange had broken off. Not only that but I found that the fingers on the pressure plate were severely damaged and that the teeth on the flywheel had damage as well.

I wasn't expecting this and was disappointed to find these problems. Of course this meant that I would have to spend more money that expected to replace parts that I assumed would be fine. But more disappointing was the fact that all of this was likely caused by me and my inexperience.

New Parts

I decided to replace some additional parts while I had the engine out. Some of these parts were to address known failure points while other parts where for increased performance.

My long-term goal for this car is to make it as fun as possible to drive while not making it unbearable on the street. This included stiffening up the chassis, suspension and various linkages and mounts. I had already replaced some of the bushings in the shift linkage which provided a minor improvement. Next on my list was to stiffen up the engine and transmission mounts. While these mounts were significantly stiffer than OEM, the were still soft enough to be relatively comfortable on the street. With the windows up, more transmission noise creeps into the cabin. And when the A/C cycles, there is significant vibration transmitted into the chassis and steering wheel. However when driving the car on a nice day with the windows down, these are non-issues.

To Be Continued…

New STI Group N engine mounts on the left. OEM engine mounts on the right.

A beautifully machined aluminum piece that deletes the Tumble Generator Valves (TGV) from the intake path. Sadly I had to remove these parts due to COBB Tuning no longer supporting this modification and not being able to clear the error code from the car’s ECU.