Staying Power

Reproduced with permission
from a feature story in Auto Accessories Buyers Guide #4.

"It's not what you'd call a classic upgrade," Brett Middleton said. "We are talking a successful businessman, the sort of man who drives a Range Rover and a BMW, who wanted to build a known performance car. "So he bought a new WRX and spent another $40,000 on it."

Visually, it's an understated, almost plain-looking car, apart from the wheels and lowered suspension. It doesn't even have a WRX tail on it. Instead, the money was mostly invested under the bonnet and under the car. The Engine output shames even an STi and more importantly, the motor has been built to handle it, with all of the important internals upgraded. Ditto the suspension, transmission and brakes.

It's stuff you can't see, its not "classic upgrades," which often focus on appearance, a sporty exhaust note and little else.

The Subaru's owner is a busy, modest bloke, happy to let Brett do the talking, just as he entrusted Brett's company, MRT Performance in Ryde (Sydney), to transform an already exciting coupe into a serious "weekend fun car". Weekend fun includes lap dashes and club days at the track.

Brett Middleton is a multiple Australian rally champion and highly regarded race car builder, so is expert at building finely-balanced performance cars with the dynamics and strength to handle the pace. His firm specialises in performance four-cylinder sedans, everything from Hondas to Daihatsus, but Brett admits that 80 per cent of his business at the moment are WRX Subarus.

Looking first at the motor in our beautiful blue feature car, the engine was completely disassembled, the blocked chemically cleaned and the bores honed. MRT forged pistons were fitted, together shot-peened and crack-tested conrods and ARP bolts. The pistons and combustion chambers were ceramic-coated for additional protection.
The reason for all this care and effort was the significant power increase Brett was planning from a combination of Subaru Technica International (STi) parts and an M48 Pro MoTeC engine management computer.

STI bits comprise the turbocharger, injectors and camshafts, as well as the viscous-coupling centre diff which distributes power to all four wheels.

"This is the first serious STI 'version 5' upgrade done in Australia," Brett said. To give you an example, the camshafts alone took three months to be supplied by STi." A heavy-duty clutch and complete sports exhaust were also fitted, together with fuel rail mods to improve fuel flow as well as the miss match in the delivery that greatly effects reliability, it certainly likes to drink when pushed.

When we took the pics, the car was in the process of having a front-mounted intercooler installed. When this is done, the car will be dynoed (no easy job on an all-wheel-drive car), with an expectation of power well in excess of the STi, which claims 206kW at 6500rpm.

Suspension and brakes have been upgraded to suit, the latter in spectacular fashion with trick four-piston AP racing brake callipers up front. Sway-bars, link kit, anti-lift kit, camber kit and lowering springs (developed in consultation with MRT) are matched to adjustable shock absorbers.

Wheels are 17 x seven -inch TH type Compomotive Motorsports, distributed by MRT, fitted with 215/40/ZR17 Dunlop Formula W-10 tyres.

The interior is standard apart from a shift light mounted high on the dash, a terminal mounted in the glove box to download data from the MoTeC, and a Momo suede steering wheel. Auto Accessories was offered a brief spin in the car. It makes delightful turbo and induction noises (absent on standard Subaru's, even STi's) from 3000rpm on, and an unobtrusive growl from the exhaust as revs build higher. Like the STi, the power starts from 3000rpm, gets serious from four, then all hell breaks loose as it screams from five to six and a half. Top stuff!

Brakes feel wooden tootling around the suburbs, but offer enormous power and exquisite control on the pace. I'd love to try them on a race track.

Ditto the suspension, which was set firm. This is as it should be in a car that is used only occasionally and always for fun, but Brett assured me the shocks can be quickly adjusted (with external damping controls) to provide a much more compliant ride for everyday use.

There is much other detail that we haven't discussed here, including careful setting up of virtually every component, and I was left in little doubt that the owner got his money's worth. In practical terms, his WRX is as fast as any car on the street, and probably handles better and stops quicker. Equally important, it has been built to do it reliably and safely for as long as the owner desires.

The Goodies -1999 Subaru Imprezza WRX Body Stuff:
	Stock but with WRX decals removed.
Engine Room:
	Treated Rods MRT forged ceramic coated pistons STi Turbo unit, Injectors and Camshafts. Motec M48 Pro ECU Front mounted intercooler Sports exhaust Heavy duty clutch STi viscous coupling
Running Gear:
	Sway bars, anti-lift kit, camber kit, and lowering springs. Koni adjustable shocks Four piston front brake calipers 17 x 7 inch Compomotive alloys 215/40 Dunlop Formula W-10 tyres