Driving Sports

Subaru makes some fast factory cars. Specifically, its rally-bred STI is known for a 300hp fire-breathing mill and excellent road-handling capabilities. However, as much as I like speed, I prefer to have something a little less “racer boy” for my daily driver. I like the feel of Subaru’s boxer motors and the driver ergonomics, I also happen to run a Subaru magazine, so it only made sense that I looked elsewhere in the ‘roo family when selecting a car for my own. In the end I chose a model with styling and an interior I could live with every day: a 2007 Subaru Legacy GT.

Stock, the Legacy GT has a 243-hp (crank estimate) turbocharged motor that shares many components with the STI. Though, unlike the STI, you can get leather, a moonroof and body styling that doesn’t look like it was an afterthought. In fact, I’d say the 2007-08 Legacy is one of the better-looking cars on the road today.

Of course, given my occupation, this car didn’t stay stock long. Shortly after break-in we started the first phase of changes in the “need for speed” category. This included a larger turbo, fatter top-mount intercooler and a Perrin turbo-back exhaust system. All the parts were tuned using an ECUTek reflash and netted a tidy 280hp at the wheels

I ran that config for a good year and was pretty happy with the overall performance: the 18G Blouch/TDC Turbo spooled fast and had enough scoot for the occasional track day or Time Attack race. The Achilles heel was the top end. Power came fast, but didn’t stick around, making long straight-aways on the track my nemesis. Also, in hot conditions, such as I faced at the 2007 Tuner Shootout in Nevada, the top-mount intercooler just couldn’t keep temperatures at bay.

Before we started on “Phase 2“ of this Legacy GT build, my technical editor Tim Bailey and I changed the engine management to a Cobb Accessport 2.0 (it wasn’t available for the car’s CANBUS system when we did Phase 1) and played around to see if we could break 300whp mark with the existing configuration. All indications were good, but then made a mistake, by pushing the tune with stock injectors and “trying some stuff” in an uncontrolled situation, followed by me flogging the car around our test course. That mix spelled disaster for piston #4: we broke a ring and smoking immediately followed. This is otherwise known as the “change engine indicator” coming on. Yes kids, don’t try this at home, we’re professionals.

In the tuning world the death of one engine often leads to the development of a newer, stronger mill to replace it. This project is no different. Out with the stock (busted) shortblock, and in with a brand-spankin’-new STI block with a special ingredient: Cosworth forged pistons. This was assembled for us by the guys at PDXTuning in Portland, Oregon.

While the motor was out, we finally installed some larger injectors (from our friends at Deatschwerks), slapped on a larger AVO 420 turbo (installed by Rallitek performance), and fitted a Perrin front-mount intercooler to help keep temperatures more consistent. The clutch was also fried, so in went an ACT heavy-duty clutch kit along with the ACT streetlite flywheel. If you’re keeping score, yes, not much of the original confirmation remained when all was said and done.

For the tune, we took the car to Steve’s Pacific Import Auto in Tacoma, Wash., where Tim Bailey (Subiesport Magazine's technical editor and owner of Surgeline tuning) was finally able to put together a proper tune on their dyno. End result? 320 wheel-horsepower and 320 ft-lbs of torque, measured at the wheels on the Mystang dyno, running 92 octane fuel.

Unfortunately, I can’t give you all the facts about this new build, since it is an ongoing project car for Subiesport Magazine, and is scheduled to appear in an upcoming issue -- we have to keep some morsels for the magazine. But I can say this: It’s fast, but not fast enough. Certainly faster than any stock STI, but that’s not what I want. I don’t think I’ll be happy with this setup until we hit or surpass a safe 350whp, which will require some more changes.

The fact that we’re not done yet is okay by me. In many ways, testing all these different setups is more fun than the destination itself. Stay tuned, as the adventure continues.