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A Forester's Journey to an STI

We here at GE3KSPD love nothing more than DIY car projects, especially the ones that transform your average cars into street savages. When we met Michael and his beautifully done Forester STI, we instantly knew we had to share it with the world. It's not a car that you see everyday, hell, it's not a car that you see almost ever in this part of the world. We asked Michael to give a brief history of his build and what prompted him to even attempt it. Enjoy!

I originally bought the car back in 2009. It was my first ever Subaru, a bone stock 2001 Subaru Forester in manual transmission. I bought it off of some school teacher way up in northern NJ after months of searching. I really would have liked to have gotten maybe an RS or WRX/STI, but they were both hard to find and very expensive at the time coming out of school and starting a new career. Right off the bat, I didn’t imagine it would be anywhere near as involved and complex as it is now in 2015, but I was really inspired by the 98-02 Japanese Forester STIs (Yes, this was a real thing!)

So fast forward to 2011, I had done some basics such as intake, exhaust, coilovers and other suspension mods, but those only went so far. After some serious researching and hunting around, I stumbled upon a small crowd of people on the Forester forums who had done full WRX or even STI swaps. I did a vast amount of researching before coming to the conclusion that it was something I wanted to do. With a large amount of help from a friend (who happens to be the owner/operator of Procom Racing, Lou), I was able to start aquiring the parts and necessary items to make the car work. It was no easy task to make a 2001 Forester run a full 2005 STI swap front to rear. In fact, there were quite a few setbacks during the process of converting it. What you ended up with at the finish line was pretty much a Frankenstein of mixed parts from different years, run by a professionally tweaked and merged wiring harness that allowed me to run every single component out of a 2005 WRX STI in a 2001 Forester. By 2012 it was on its feet, kicking and screaming, turning a lot of heads in the process.

So as far as mods go, that’s hard to put into a perspective. I always found it hard to make a direct list of what "modifications" had been added, seeing as the car was basically stripped to bare and completely rebuilt with parts of another Subaru model. The only stock parts that are left on the car are the dashboard with wood grain trim, climate controls, and under the hood maybe the stock ABS unit and washer fluid unit. Outside of that, everything- and I mean everything, has been swapped out, right down to the interior carpeting, seats and mats.

Basic rundown:


Fully built 2005 WRX STI long-block (New from dealer)

Blueprinted and built by PROCOM Racing

Manley Rods and Pistons

ACL bearings

Nitride Crankshaft

ARP head studs

Brian Crower stage 1 head package

TGV deletes

KS tech intake and inlet

Perrin large Top Mount Intercooler (with water sprayers)

DW 740cc injectors / Walbro fuel pump

NGK one step colder spark plugs

JDM EJ20GT headers

Grimmspeed up-pipe with 38mm Tial External wastegate

Grimmspeed 3-port Electronic boost controller

Cobb catted full turbo-back exhaust system

Cobb Accessport (selfpro-tuned)

36mm KOYO aluminum racing radiator with Gates water pump / timing belt kit.


Full 2005 STI 6-spd transmission with R180 rear differential

MAPDCCD aftermarket DCCD differential controller

Many assorted Kartboy bushings and hardened engine/tranny mounts

Exedy stage 2 clutch kit

Kartboy short shifter kit

Whiteline driveshaft bushings / mounts

Beatrush rear differential support


2005 STI Brembo brakes

DBA rotors

Hawk Pads

Technica Stainless steel brake lines all around

WRX STI brake master cylinder / booster


Feal re-valved factory 2005 STI struts

Group-N tophats

RCE yellow springs with 1" subtle tophat spacers

Cusco front and rear strut tower bars

Perrin Front and rear swaybars (including enlarged mounting brackets / supports)

Cusco B-pillar bar with 4-point harnesses

Cusco rear differential support braces

Cusco Fender braces

Whiteline swaybar endlinks (front / rear)

2005 JDM STI front control arms

2005 STI rear control arms

Whiteline extended tie-rod conversion kit

2004 WRX STI front sub-frame

2004 WRX STI steering rack (quicker ratio)

Whiteline steering rack solid bushing kit

Group-N Solid Pitch mount

All crossmember bushings swapped to Whiteline.


2001 JDM Forester hood