HSV's swansong Aussie supercar comes into focus as performance testing gets underway

Sources close to the project have indicated the vehicle in question will arrive in showrooms – at least a couple of selected ones before they all go to owners – in the second quarter of 2017.

Positioned one rung above the 'regular' HSV GTS-R, the W1 is expected to be powered by a monstrous 476kW supercharged V8.

And forget 0-100km/h times – this car will be about 0-200km/h and quarter-mile numbers.

Since it was being towed by a Holden Colorado Z71 very early in the morning heading south out of Melbourne in the direction of Holden's Lang Lang proving ground, we expect this W1 is about to undergo extreme performance testing over the next few days.

This pre-production model is our best look yet at what motorists will frequently see when the HSV GTS-R W1 hits the road – the rear-end as it blasts away from traffic lights. There is an LSA badge visible, but bear in mind this is a pre-production model and HSV will be slinging the LS9 engine in mules, especially those with extra camouflage.

The most prominent feature is the aerodynamically-formed rear wing, which gets extra struts within its structure. Sure, they look cool but probably add extra rigidity, which will be useful at the high speeds the GTS-R W1 will be capable of.

HSV has plenty to hide... for now
This latest spy photo also shows the 2017 HSV supercar wearing psychedelic camouflage on its flanks for the first time too. The reason? HSV is has something to hide.

It doesn't appear as though the car has a wide body kit but clearly the company has added unique styling flourishes, which extend to the rear apron and presumably the front fascia too.

As we've reported, other unique W1 features will include non-adjustable Supashock billet dampers, more powerful six-piston AP brakes and unique 20-inch alloy wheels.

Powered by a 6.2-litre engine believed to be the Chevrolet LS9 sourced from the Corvette ZR1 supercar, it outputs 476kW and 820Nm in the 'Vette.

Expect similar numbers for this Aussie beast, which will be available exclusively with a six-speed Tremec transmission and should tap 100km/h in about four seconds and the quarter-mile in around 12.

Therefore it will be the most powerful, most sought-after, most collectible and potentially the most valuable HSV ever made.

Without doubt it will be fastest road car to ever wear the Holden Special Vehicles badge, a bittersweet fact considering it will also be the last Aussie-made HSV before its donor car, the Holden Commodore, ceases production late this year.

Despite an expected price-tag of around $170,000, HSV dealers are being inundated with cash deposits from customers keen to put their name next to a GTS-R W1, which will be limited to around 250 vehicles. The standard GTS-R will be unlimited.