Aston Martin’s Valkyrie V12 makes a Honda VTEC seem about as free spinning as a Duramax diesel. Developed by legendary engineering house Cosworth this naturally aspirated 6.5-liter V12 develops 1000 horsepower at 10,500 rpm and doesn’t stop spinning until the hard limiter kicks in at 11,100rpm. Yeah, 11,100rpm.
“If you don’t come away frightened there’s something wrong with you,” laughs Cosworth MD Bruce Wood as he leads us into the control room to hear the engine run through a simulated lap of Silverstone on the dyno. Frightened? If I’d had a can of mace I would have been spraying so hard the whole room would have looked foggier than a Victorian night in London. This thing sounds like pure evil. And it’s not just the shriek; a sonic portal back to Sundays spent watching Formula One in 1995. It’s how quickly it spins up as it runs though its Ricardo-built single-clutch transmission.
Dean Smith/Aston Martin
The philosophy couldn’t be more different from the one being used to create the engine for the AMG One just a few miles from Cosworth’s base. While the AMG’s turbocharged 1.6-liter V6 gives it a clear link to current F1 tech, the Valkyrie’s V12 feels peculiarly un-zeitgeisty, clearly harking back to the glorious mid-1990s days of V12 F1 cars. No surprise, given the creative force behind the Valkyrie and its powertrain is legendary F1 engineer, Adrian Newey.
“This is a very personal project for Adrian,” says Wood, who diplomatically describes Newey as ‘quite demanding’ in the way Pol Pot might have described him as having ‘a bit of a temper.’
Dean Smith/Aston Martin
“Adrian and Red Bull originally came to us asking for a 6-liter V12 developing 950bhp, and it would have been easy to reach these power targets by going the turbocharged route,” says Wood, whose company’s back catalog includes iconic blown motors like the YB in the Ford Sierra and Escort Cosworth.
“But no matter how good they are, there is always an element of turbo lag and a loss of sound quality. There are packaging problems too. But ultimately, we felt, and Adrian felt, that if your main objective is the driving experience then the best option is a naturally aspirated V12.”
Dean Smith/Aston Martin
Unfortunately for any of you billionaires reading looking for the ultimate hypercar driving experience, the Valkyrie won’t be coming to the US, at least not officially. Even at a rumored list price of around $3m for each of the 150 cars (which are all sold anyway), the costs of homologating for the US market were deemed too expensive.
So here’s what we’re missing:
For a start, like most high-level racing motors and Ferrari’s F50 V12, but almost no other road cars, the engine is a structural component of the car. Those giant ears on top of the cam covers are where it bolts directly to the back of the carbon monocell.
Dean Smith/Aston Martin
There’s more. To save weight and reach Newey’s ambitious 441lb weight limit there are no liners, just a plasma coating on the cylinder walls. And the four cams (each featuring variable valve timing, but not variable lift, which can’t react fast enough) are driven by gears, not chains, just like a proper racing engine. ‘You can’t guarantee the reliability of chains beyond 10,000rpm,’ says Wood.
But because cam gears whine and rattle, and the back of the carbon chassis tub separating the cockpit from the engine bay acts like a giant drum skin enhancing sounds, it would have been too noisy. So Cosworth pushed the chains to the back of the engine. That added a few ounces, but even the finicky Newey agreed it was for the best.
And then there’s the hybrid element, a single-motor F1-style KERS system developed by Croatian firm Rimac. Officially, Aston isn’t yet saying exactly how much, but an Aston sourced hinted at around 125bhp. But unlike the AMG, which uses four electric motors, two of which drive the front wheels, the Aston is rear-wheel drive, sending both power outputs to the rear axle. There’s no EV mode.
Dean Smith/Aston Martin
Wood claims that Cosworth shied away from using the latest sci-fi materials whose reliability wasn’t wholly known, preferring to use the best of established stuff. So there’s aerospace quality alloy heads, and titanium rods and valves, but it’s all proven tech. And while the engine lifespan isn’t going to worry a small-block Chevy, Aston’s V12 will last at least double the 31,000 miles AMG says it’s motor will need between rebuilds. Maybe more, according to CEO Andy Palmer:
The engine has already undergone a successful 200-hour accelerated dyno test, replicating 100,000 miles. And that’s before it’s even turned a wheel in Valkyrie tests.
“Our expectation is that by 100,000km (62,000 miles) it won’t have blown up, but some of the components will be worn out,” says Wood, before adding: “not that many owners will ever get anywhere near that figure.”
But Cosworth subjected the engine to over 200 hours of dyno testing (‘much of it at full throttle’) to make sure they would last the course without needing a tear-down after every third Sunday drive. The service requirements are relatively modest give the spec, comprising an oil change every 3-4000 miles.
Dean Smith/Aston Martin
There’s much more detail to come about areas like the torsion bar suspension, the hybrid system, the aerodynamics and, of course, performance, which Aston admits, is massively focused on lap times and not standing start acceleration. But for now, just take another listen to that screaming naturally aspirated V12. It’s the sound of a near-dead technology rising up for one last epic battle, like the monster in a zombie flick mustering the energy for a final attack the moment your back is turned. It’s the sound of a world of car fans acknowledging that we’ve lost something in the switch to turbocharged power. Drink it in because it’s unlikely we’ll ever hear anything like it again.
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