Is Ford's Falcon XR Sprint Australia's quickest car?

Unlike most of its rivals, Ford has a policy of not stating performance figures for its performance cars, the Blue Oval preferring to let the press determine just how quick and fast its cars are.

So that's just what we did this week in Tasmania when Ford Australia launched its last ever homegrown performance models before Falcon production ceases forever on October 7.

We weren't the only ones, with a number of other media outlets arriving armed with V-boxes to determine exactly how quick Ford's finest and final Falcon XR8 and XR6 Turbo sedans really are.

News Corp managed a best 0-100km/h time of 4.7 seconds after arriving early and putting in an extra day of testing, while the rest of us made do with sporadic acceleration runs between the half-day public road loop on the way to Baskerville Raceway, where there was no time or space for straightline performance testing.

Unofficially, Ford engineers says all three Sprints offer similar 0-100 pace of around 4.5 seconds, making them about as quick as FPV's old GT RSPEC and the ballistic 400kW-plus GT-F limited-editions, which are widely credited with being the quickest Falcons ever.

But they insist a well-driven XR8 Sprint manual is the quickest, at "somewhere under 4.5 seconds", followed by the XR6 Sprint auto – which is easily the quickest ever six-cylinder Falcon and the quickest Australian-made six-cylinder -- and then XR8 Sprint auto.

To be clear, four and half seconds is still a tenth or so slower than the best Australian-made production car from General Motors, HSV's 430kW/740kW blown 6.2-litre GTS.

When it was launched in 2013, HSV said its new flagship could hit 100km/h in 4.4 seconds and cross the quarter mile in 12.3 in both six-speed manual and automatic guise, making it quicker than the limited-edition 7.0-litre HSV W427 -- the fastest Australian production car until it was challenged by the FPV GT and the GT F special.

Outpowering the GTS on the dyno in 2014, the GT F boosted Ford performance to new heights with a stated 351kW and 650Nm, but just over 400kW in overboost.

Officially, the XR8 Sprint's newly calibrated 5.0-litre Miami supercharged V8 offers 345kW of power at 5750rpm and 575Nm of torque over a fat 2220-6250rpm on 95-98 RON premium unleaded, swelling to a wholesome 400kW and 650Nm in overboost.

The guys who engineered the last Falcon XRs admit that it takes plenty of finesse to extract the best time from XR8 manual and, thanks to a stiff clutch, the inability to dial up more than 3500rpm with the clutch in and a notchy six-speed shift gate that makes the crucial first-second shift difficult, they're not wrong.

Basically, it's all about technique. Don't dump the clutch but slip it with just the right action, because even with all that grunt on tap, the grippy new 19-inch 265/35 Pirelli P Zero rubber will grip and bog you down without a bit of clutch feathering.

During our brief drive we managed a couple of sub-five-second runs, but nothing to write home about. We never had access to an XR8 Sprint auto, which employs the GT F's six-speed ZF auto calibration, so we await a more thorough test in the right conditions.

The XR6 Sprint, on the other hand, proved blisteringly quick with every run, no matter how lazy on the pedals we were.

Officially, Australia's most powerful six-cylinder engine (and the only all-Aussie production engine), delivers 325kW at 6000rpm and 576Nm at 2750rpm – conveniently 1Nm more than the XR8 and well up on the 270kW/533Nm figures of the standard XR6 Turbo it replaces, and the 310kW/565Nm outputs of the old FPV F6.

But then there's the official overboost figures claimed by Ford for the first time for its beefy Barra turbo-six, which is based on the higher-compression XR6T engine (8.7:1, rather than the F6's 8.5:1) but adds the F6's larger turbo, bigger 82mm injectors and 50 per cent bigger intercooler, plus a new lower airbox and Ford-first carbon-fibre air intake with 45 per cent better air flow, stiffer GT F transmission mounts, bespoke engine calibration with individual boost maps for each gear ZF auto calibration and, for the first time, launch control.

Ford claims 370kW and the same 650Nm torque peak as the XR8 Sprint in 10-second transient boost mode when conditions (read: intake manifold air temperature) allow, which not only peaks above 14psi earlier and for longer than in the F6, but resets with every gear change.

Given you're unlikely to spend a lot more than 10 seconds in any given gear during enthusiastic use, and that Ford guarantees there's never less than the nominal 325kW/576Nm outputs available, it's a recipe for rapid, repeatable standing-start acceleration and bullocking in-gear flexibility.

We have to say, though, that the XR6 Sprint doesn't feel that quick off the line. Thanks to the extra rear grip and sweeter suspension, there's none of the tyre-turning shenanigans of the old XR6T as it struggled to get its power to the ground.

In fact, all our launches were so placid and fuss-free – time after time, no matter the road surface – that we began to think Ford's final XR6 Turbo had gone backwards.

So we persevered with a few more, with traction control on and off, with Sport mode and without, in drive and manual modes, and stepping off the brake before and after the engine reached its 1900rpm stall speed.

Sure, there's a moment of tyre squeal as the tranny shifts up just after 6000rpm and the rear hoops lose traction as second gear engages, momentarily activating the ESC and shutting three cylinders down, but otherwise all our standing starts were the picture of efficiency.

That's no doubt due not only to the extra grip, but the fact that – unlike the old XR6T, which in overboost was unofficially good for about 330kW and 650Nm – torque is limited to 550Nm in first gear.

The result is standing-start launches tame enough to make the XR6 Sprint feel a little sedate off the line, so much so that it wasn't until we downloaded the V-box data and checked our back-up shots of the screen after each run (pictured) that we realised how quick it really is.

What looked like a handful of 4.8-second 0-100 initial passes were actually 4.6 seconds, with 60km/h coming in a respectable 2.4 seconds in each case, and a couple of subsequent runs all yielding less than five seconds.

That's quick by any measure, especially considering we had no choice but to test two-up with a full tank and at least 30kg of luggage in the boot. In the old XR6T, that would have provided vital extra grip, but with the upgraded Sprint chassis it's just extra ballast probably worth a couple of tenths.

Subtract that from 4.6 sec and extrapolate from the 0-100 number a 12.3-second standing quarter-mile time, and you've got the same acceleration times as the benchmark GTS without trying very hard.

Of course we'll undertake a more definitive track test of both Sprints and their HSV rivals as soon as possible, but for now it's clear that while the XR8 Sprint manual may be even quicker in the hands of pro, the XR6 Sprint is at least as quick as the already-fast XR6T it replaces and perhaps even quicker than HSV's finest, which costs close to $100,000.

Words is both Holden and HSV are both planning something special to send off GM's homegrown Commodore next year, but right now it appears Ford's XR Sprints can claim the mantle of Australia's quickest production cars.