Launched in 1999, the venerable 6.0-liter V-12 has served Aston Martin well for the past decade and a half. Its roots are in the Ford 3.0-liter Duratec V-6 of that era and, apart from marketing purposes, it’s really a 5.9-liter 60-degree V-12, displacing 5935 cc. Over the years, the engineers in Gaydon managed to turn it into one of the more exciting engines on the market, with sharp throttle response, strong high-end performance and a stirring soundtrack. The downside: It’s a gas guzzler by modern standards, so change needed to happen. Revealing the replacement engine at the International Vienna Motor Symposium in late April, Aston’s chief engineer Brian Fitzsimons put it this way: “Further evolution of the current V12 as a naturally aspirated engine was not an option due to the environmental and legislative landscape that existed and was continuing to evolve.”
The solution? Downsizing and turbocharging. The new engine is a 5.2-liter, 60-degree V-12; it is more oversquare with a 89.0 mm bore (same as before) and 69.7 mm stroke (reduced from 79.5 mm). Aston added two twin-scroll turbochargers, one for each cylinder bank, retained port fuel injection (saying that makes emissions treatment easier than with direct injection), and added a cylinder deactivation function, which can shut down an entire cylinder bank. The engineers adopted a system that keeps the valves operating normally on the deactivated six cylinders, rather than shutting them down as some other manufacturers do. As is common, the engine periodically switches which bank of cylinders will be deactivated under low-load conditions, as when cruising at steady highway speed. Oh, and the engine is ready for start-stop technology, and runs with 0W-20 oil, all measures that improve fuel economy.
For packaging reasons and to increase total efficiency, Aston Martin decided against a dry-sump lubrication system, instead optimizing their wet-sump design to perform under the high g-loadings sustained when owners drive on a track. This system was developed simultaneously with the engine; final testing and validation took place on the high-speed track in Nardo, Italy.
The result: More than 600 horsepower at 6500 rpm and at least 568 lb-ft of torque arriving at a low 1750 rpm. In the last Vanquish we tested, the former naturally aspirated V-12 produced 568 hp at 6650 rpm and 465 lb-ft @ 5500 rpm, reflecting numerous upgrades over the years since it debuted with 414-hp/398 lb-ft ratings. Conscious that turbocharged mills are often criticized for their muffled sound characters, engineers tuned the sound of their new V-12 to match its performance: Aston says it aimed to deliver “a dominant 3rd and 6th engine order with additional sub-firing orders for a richer and deeper character;” moreover, resonance is optimized “for a more distinct edge leading toward a crisp crescendo at high engine speeds.”
On November 19, 2012, Aston Martin fired up the first demonstrator; it performed so well that the project was green-lighted in January 2013. It was ready for tooling in May 2014, and the Ford-operated engine plant in Cologne, Germany will start building the new engine next month. We look forward to getting behind the wheel of a production car, especially after hearing the engine during our drive of a prototype DB11. You can hear it in this Aston teaser video released earlier this year.
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