Cold, hard numbers. You don’t often admire an accountant. But when you have to award something as big as this, you want the authority only digits can deliver.
This battle between Ford’s last pair has been brewing a long time. Traditionally, the hottest Falcon’s packed a splayed eight. But when Ford Oz cooked up a turbocharged XR6 in 2002, suddenly the XR8’s halo didn’t shine quite so bright. And the measly 6psi flowing through its snail hinted that, if FoMoCo so wished, the range-topping Falcon could be a blown six-pack.
This split the Falcon faithful, with the XR6 Turbo vs XR8 rivalry raging ever since, nowhere fiercer than online, with few chances to settle the debate on an even playing field, until now.
As Dearborn read the Falcon the last rites, Aussie engineers used the Sprint program to unleash their considerable talents on both variants – one last chance to decide which engine powers Australia’s fastest production Falcon.
Need proof the gloves were off? While the XR8 Sprint’s blown 5.0-litre V8 musters 345kW/575Nm, the XR6 Turbo Sprint’s 4.0-litre six drums up 325kW and 576Nm – that one extra newton metre crowning it as Australia’s torquiest-ever engine.
But we’re not calling this fight from the spec sheet. We’ve set both against each other on the circuit and drag strip, and used the cold hard numbers from each stoush, in their entirety, to decide the fastest last Falcon on these pages.
Ford doesn’t quote official acceleration figures for either car. However, liquor up Ford’s engineers and they’ll reveal both automatics should nail 100km/h in around 4.6sec, while a manual (available only in the XR8 Sprint) could improve that by another tenth.
You can imagine our disappointment with our first XR8 Sprint’s times. We couldn’t blame conditions, as the sun was high above Heathcote Raceway in rural Victoria, the air cool and our automatic example on correct tyre pressures and toting a quarter tank.
But no matter what we tried, the XR8’s precious Pirellis couldn’t push it to 100km/h any faster than 5.07sec. A 182.35km/h trap speed was fitting of its overboost-induced 400kW/650Nm, but its 13.14sec quarter couldn’t dream of becoming a 12 with such rampant wheelspin during launch.
Our second crack at Heathcote came a month later, except this time an XR6 Turbo Sprint was on hand to see if two fewer cylinders were a better bet. As it turns out, they were. It hit 100km/h in 5.01sec and crossed the quarter in 13.12sec with 180.39km/h on the dial. Meanwhile, the XR8 Sprint trailed with a 5.26sec 0-100km/h time and 13.22sec quarter.
The XR6’s trick lay at the start line. Turbo lag (the XR6’s peak twist arrives 450rpm later at 2750rpm) gave its rear bags a chance to hook up while the XR8 simply hosed its hoops with too much torque, making it “a bitch to launch” – to quote Morley – even with launch control.
Moving the duel to Winton Raceway at Bang For Your Bucks only confirmed the six’s knack.
Although this new XR8 Sprint wore fresher tyres than the last examples, its DIY-shifter made launching exceptionally difficult. After seven attempts, twice that of the XR6 Sprint, it passed in a best 0-100km/h time of 5.03sec and 13.05sec quarter. Our fastest run yet, but not enough to catch the six.
Our XR6 Turbo Sprint revelled in Winton’s repaved surface, its ZF six-speed auto’s launch-control making the process a simple two-step affair. After clearing the hole it ticked off 100km/h in 4.89sec and 400m in 12.89sec.
The XR8’s extra power only chipped in at the trap’s radar. Its 185.48km/h at Winton just pipped the XR6’s 184.11km/h and suggested it’d reel in the Turbo if given enough tarmac.
You’d think, then, the XR8 would trump the Turbo on a roll from 80km/h. Now we’ve done three 80-120km/h runs with the eight-pot, and two with the six, and you couldn’t floss the gap between the average of each data set, because there isn’t one. Both cars will, on average, evaporate the overtaking increment in 2.66 seconds.
The XR6 Turbo Sprint might be down 30kW on overboost, but it dials up an identical 650Nm during the 10-second window. It’s this, and its 54kg slimmer hips, that allow the XR6 Sprint to punch just as hard from lower rolling speeds.
So far as we’re concerned the XR6 should nose ahead on a strip everytime – unless you’re on an airfield. But while we’re happy to crown one the strip king, a question-mark still hovers over those unattainable 0-100km/h times.
We’re not saying the Sprints aren’t capable of proving their engineers right. Internet forums report they’ve achieved such times with the same cars we used. However, because we can’t verify the runs or the conditions in which they were tested, we can’t help but see them as too optimistic. Or maybe our stars just never aligned.
Would the Sprints’ legacy prove more definitive on track? With a Driftbox plugged in and Warren Luff at the wheel, we snaffled both away for a secret track battle at Bang For Your Bucks to find out.
To be honest, with 24kg less to point at corners, and a further 30kg less resting on all tyres, we expected the XR6 to rip around Winton faster. Its 1:40.7sec lap was already nine tenths clear of last year’s XR8 (albeit on a new surface) and 2.6sec faster than an F6 Typhoon. But surprisingly it was the XR8 that emerged the clear star, its 1:38.4sec lap tearing 2.3sec out of the XR6 Turbo’s time.
Both cars wear the same rubber, brakes, and suspension hardware albeit with unique tunes. So what was the XR8’s ace? While its drivetrain couldn’t exploit a drag strip, it proved a juggernaut on the race track.
Peeking at the XR8’s data trace reveals it had piles more speed on every straight. No matter the length. Not only did it extract an extra 10km/h from Winton’s main drag, with 189.38km/h playing the XR6’s 179.88km/h, it carried 8km/h more between corners 11 and 12 – a section where Luffy would’ve barely straightened the steering wheel.
The stark difference in urge came down to the XR8’s stonking supercharged eight. While the XR6 would start to gasp near its 6200rpm redline, the XR8 simply pulled harder as the revs climbed higher.
The XR8 was stronger on the picks, too, neutralising 100km/h in 36.73m as opposed to the XR6’s 37.16m. Along with a longer stop, what the data didn’t reveal about the XR6’s anchors was the dull feedback, despite it using the same six- and four-piston Brembo arrangement as the XR8.
Combine the XR6’s numb brakes with a six-speed auto that didn’t rev on downshifts, which Luffy said over-slowed the car, and the six was sometimes slower into corners as well as out of them. Turn 12 is a classic example, where it wipes off more speed during braking, but exits the corner with 2km/h less.
In the tight stuff the XR6 Turbo Sprint was better, taking Turn Nine’s apex 4km/h faster than the XR8. For reference that’s only 0.1km/h slower than an MX-5, its lighter nose proving a more agile ticket.
Stepping back to look at all the data draws interesting conclusions. You certainly wouldn’t predict the less-powerful Sprint claiming the strip and the heavier one the circuit. But picking a winner?
On one hand you could argue there aren’t any switchbacks on the way to Woolies, and therefore, straightline stonk should matter most. On the other, you could say drag numbers are too one-dimensional and ignore a car’s full performance potential.
To cut it fairly though, nothing beats objectivity. And to settle this we’ve defined each car’s performance just as Bang For Your Buck’s trusty formula does. We’ve arrived at a winner based on the Sprint with the most points. You can refer to the above breakout for a more detailed rundown but, as it reveals, the fastest ever production Falcon is… the XR8 Sprint. Surprised? Disagree? You know our email address.
Many would consider the 351ci V8-powered GT-HO as Ford’s greatest Falcon (you’ll have to wait 23 pages to find out whether we do), so having a six-cylinder bobbing up as the fastest ever just before the credits roll would’ve been a bit awkward. And, the V8’s gruff burble and blower whine just sound right.
That doesn’t detract from the XR6 Turbo’s greatness, though. If emissions killed off the V8 long ago it still would have made a brilliant end stop to the legacy. Along with its stomp-and-hang-on drive experience, its special Barra, infused with F6 bits, is an all-Aussie legend. Which is something to be proud of on its own.
However, as an accountant knows, you can’t argue with numbers. All hail the eight.