Ever fantasised about flogging a V8 Supercar on public roads, wowing pedestrians and leaving big, black liquorice strips everywhere? Me neither.
But there are people out there who dream about such things and buy a 430kW HSV GTS to satisfy this urge, only to fang it for a week and get bored.
To keep this admittedly small market entertained, Melbourne-based tuning gurus Harrop Engineering have built this: a GTS with 580kW, 1100Nm, a manual gearbox, wild headers and a cat-back aftermarket exhaust with Tourette Syndrome. “One with the lot”, as Harrop puts it. They call it their Stage Three kit.
Let’s start with Stage One. You get a cold-air intake, smaller blower pulley for more boost, colder thermostat, solid drive coupling for the supercharger and a re-tune, yielding 500kW/900Nm. That’s up from the stock 430kW and 740Nm (which Harrop has verified on its dyno).
Stage Two adds an overdriven crank pulley, more boost, bigger injectors and another re-tune for 530kW and a stunning 1000Nm – over 25 per cent more than stock. Harrop will also warrant your driveline up to Stage Two.
It’s when you get to Stage Three, though, that “you’re on your own” when it comes to warranty, which then only applies to the bits Harrop bolts on, but nothing else. This is the package on the car pictured above.
On top of Stage Two, it has an even larger overdriven crank pulley, yet more boost, an angry cam, ported heads and another re-tune and makes 580kW (that’s 778hp!) and 1100Nm.
Or more than a V8 Supercar which, while having a better power-to-weight ratio, doesn’t try to put its power through road tyres like our test car pictured above, demonstrating what happens when you do such silly things to a car.
Harrop invited us to drive this Stage Three GTS which actually belongs to a customer who kindly lent it to us for this story. We agreed, and gulped.
It looks stock from the outside, save for some little ‘580’ stickers that, understated to the point where it’s almost comedic, hint at the monster under the bonnet.
The interior is stock, too, and everything works. Fire her up and she’s a little louder than usual as the big cam rocks the car around like an old Beaufighter. But meandering through traffic, it is bewilderingly well behaved for such a wildly-tuned car.
Straight bit of road. Press the throttle towards the floor and, well, wow. You have to ease into the gas like you’re feeding a two-by-four into a bandsaw. The GTS squats and hammers, unleashing a huge, endless stream of thrust.
Its power delivery is brutal, relentless, evil. Driving such an animal with a manual gearbox tests your concentration – and your ability to change gears smoothly.
Touching the ESP button tests your self-preservation instinct. Indeed, you wouldn’t leave the Harrop GTS in inexperienced hands; disrespect the throttle and it will bite you.
A generous dollop lights up the rear tyres with hilarious ease, as if they’re made of butter. Indeed, Harrop says the owner has already chewed through a few sets of rears and he hasn’t even had the car that long.
The Harrop 580’s sheer speed makes long corners – normally sweepers – feel like hairpins, particularly as its stock brakes can’t keep up. We barrelled into one corner to find ourselves nearly bending the brake pedal trying to stop. It needs pads with more bite. Badly.
The aftermarket exhaust sounds tough, too, barking its V8 roar with a ferocity we wished the stock car had a little more of.
Fuel consumption? We were too scared to look. Although worrying about such things is a bit like injecting steroids into your arms and then worrying if your jojoba oil is certified organic.
As for performance figures, we decided against testing the car on the strip during Melbourne’s January heatwave, with temps up around 45 degrees (in which the GTS performed flawlessly).
The stock GTS will hit 100km/h in 4.5sec and eat up 400 metres in 12.6sec (our times), so you could expect the Harrop-tuned GTS to easily dip into the mid-to-high threes for the 100km/h sprint, hamstrung only by its ability to put down all the power.
But, able to grab a few gears and better apply its ridiculous urge, the quarter would be something else altogether. A low eleven? A high 10? We’ll get back to you. If we survive to tell the story.
Engine: 6.2-litre supercharged V8, OHV, 16v
Power: 580kW @ 6200rpm
Torque: 1100Nm @ 4300rpm
Price: $111.050 (including modifications)