2006 Subaru Impreza WRX STI - Improved Production

When it comes to motorsport and specifically the versatility to be used in a range of categories of racing, not much comes close to the Subaru WRX STI. Synonymous with everything from gravel rallying to circuit racing, time attack to hill climbs and everything in between, the Subaru WRX STI is a very accomplished race car.

When Subaru released the “Hawkeye” WRX (as it was affectionally referred to by WRX enthusiasts), it was met with universal acclaim from motoring journalists worldwide for its sharp performance and impressive levels of grip. Even more impressive were the reviews of Subaru Tecnica International’s model variant, with its stronger drivetrain and higher-output engine. In all honesty, if you are serious about your motorsport, it is the STI that you want to own rather than the base model WRX.

And that is exactly what the current owner wanted when he acquired this very impressive 2006 example. Under his custodianship for the past five years, a significant amount of time and investment has gone into the Subaru to turn it into an incredibly capable track car. In fact if it wasn’t for another race car project looming on the horizon, it simply wouldn’t be offered for sale.

The STI is log booked for Improved Production racing however it has not seen any door-to-door racing for many years. Instead, it has been used lightly for track days and – should the new owner wish to do so – it can be readily turned back into a road going car (it is not on the WOVR). But given how capable this Subaru is on the track, we have a feeling the new owner will want to make the most of its acceleration, handling and top speed at the circuit, rather than on public roads.

Comprehensive specification list for this STI as follows.

Engine
• Built forged 2.5L bottom end
• Nitrided STI Crank and rods
• Forged CP pistons
• New heads and cams (5 years ago)
• Cometic head gaskets
• Upgraded head bolts
• Upgraded oil pump (pressure upgrade)
• Killer B Motorsport sump
• Oil system and lines upgraded
• Tuned for E85 and makes 255kw at all 4 wheels
• Upgraded fuel injectors and fuel system to suit E85
• Bosch External fuel pump and surge tank (boot)
• Upgraded fuel lines
• Process West cold air intake
• Blouch RBK Dom 1.5 XTR 8cm turbo upgrade
• 3-port boost solenoid
• 3" Silicone turbo inlet
• Set of PSR headers (coated)
• Process West front-mount intercooler
• Turbosmart blow off valve
• Link ECU management
• New Full River race battery
• Full service incl new plugs, coil pack, radiator fans, wiring check and full spanner check

Driveline
• Modena 6 speed sequential gearbox (installed Apr 2022 at a cost of $40k)
• Front 8 plate motorsport LSD full heat treated billet
• Locked spool centre diff
• R180 motorsport rear LSD
• Drop gear either 1.1:1
• 26 tooth input shaft spline for circuit racing upgrade
• Flat shift load cell gear knob
• WRX 3500 rally clutch kit with Chevy spline

Brakes & Suspension
• Brembo calipers and slotted DBA 5000 rotors (two events)
• WinmaX W7 compound brake pads
• BC Racing fully adjustable coil over shock absorbers
• Upgraded sway bars
• Goodridge braided brake lines

Wheels & Tyres
• 225/45/17 Yokohama Advan A050 semi slicks
• STI gold rims (17 x 8.0)

Interior
• Full bolt in cage (CAMS serial number 60914)
• Interior stripped
• Sabelt Titan racing seats (driver and passenger)
• Five-point Willans harnesses (driver and passenger)
• Window net
• Heated front windscreen (adjustable top/bottom/both)
• Dash-mounted gear indicator
• Performance Box GPS-Based lap timer and data logger

The Subaru has just had a major service and pre-track preparation carried out by the experts at Milldun Motorsport in August of last year. They carried out a comprehensive front-to-back review of the car – worksheets can be provided – with new fans installed, new pumps, an injector clean, dyno run-up and the car weighed.

The last time the car was out on the track (September last year) it ran flawlessly all day and the car’s owner was able to do a 1:22 at Sandown. He acknowledges that he is by no means an experienced driver so the car is likely capable of even quicker times. There is a small scrape on the right-hand front guard that was pre-existing when the current owner purchased the car. He notes that there are some marks and stone chips commensurate with a track car however aside from this, it presents extremely well both inside and outside. All graphics and sponsor stickers are removable and the owner is even willing to assist with freight Australia-wide should the buyer live outside of Victoria.

This is an incredibly capable and very fast WRX that would suit a variety of motorsport disciplines and simply could not be built for the auction reserve price. We’d absolutely love it in our garage as a weekend track toy and have no doubt it will put huge smiles on the face of its new owner.