With strengthened internals and the cooling side of the project taken care of, the team then turned their expertise to the all-important fuel system. The car now sucks petrol with an upgraded fuel pump and utilizes 800cc injectors rather than the standard 550cc versions, although Alastair admits that even these are close to their maximum flow capacity.
Once everything was assembled the initial mapping took place on the rollers and results were very encouraging as the engine produced 425 bhp, and that was on the low boost setting. There are now two further boost settings - one for 465 bhp, and the other for 500 bhp, or 501 bhp@6500 rpm to be exact, with 480 lbs/ft of torque kicking in at 3500 rpm.
"It's awesome to drive," says Alastair. "It's really smooth and very progressive and it's very deceptive; you just don't realize exactly how quick you are going until you look down at the [gauges] or have to slow down for a roundabout." At the moment the Subaru still relies on the standard Brembos to slow it down, although they will soon be replaced by a GGR 6-pot conversion with 340 mm rotors.As anything over 350 bhp is likely to give a stock clutch a meltdown GGR have sensibly upgraded this part of the transmission, but without fitting a paddle clutch, in an effort to retain some practicality for everyday use - an essential element in the project.
GGR have recently carried out a preliminary shakedown to record some performance figures and with the car on its 465 bhp setting it reached 60 mph in 4.3 seconds and 100 mph in 10.2. Alastair is confident those times will be improved on; for instance in future he'll hold the car in 3rd gear for the 100 mph dash, rather than changing up to 4th at the last minute. Top speed so far has been 174 mph.As with the majority of GGR demos cars, and we've lost count of how many we've featured over the years, they are not content with just making it go faster; they also demand improved handling. With this Impreza they have opted for Tein's fully adjustable coil over suspension kit and mated it with the EDFC (Electronic Damping Force Controller) which allows suspension settings to be changed from inside the car depending on road conditions and driving style. While Alastair would be the first to admit that it's a bit of gimmick rather than a necessity, the technology is available, so why the hell not? Fitting the complete 2350 ($4108) system isn't especially difficult. There's just some extra wires for the stepping motors. The hardest part being finding a location to mount the control unit; GGR finally settled on placing it where the clock used to be on the top of the dashboard. The unit features 16 levels of damper adjustment for both the front and rear and features three convenient programmable presets for the most used settings. The final part in this improved handling equation are the set of 19 in wheels which are shod with Toyo Proxes, which Alastair rates very highly.