The new twin-turbocharged 3.6-litre V6 produces 313kW of power and 583Nm of torque - making it the most powerful General Motors V6 ever, and also claiming to be the most power-dense six-cylinder engine in the mid-size luxury segment at 88kW/litre.
Based on the existing 60-degree 3.6-litre DOHC six-cylinder unit offered in the current Cadillac SRX, XTS and ATS, the new twin-turbo engine receives an all-new cylinder block casting, cylinder head castings, strengthened connecting rods, domed aluminium pistons, direct injection, tuned inlet and outlet resonators and aluminium cam covers.
Helping to deliver approximately 90 per cent of the engine’s peak torque between 2500-5500rpm are two turbochargers producing more than 12 pounds of boost – with guidance from vacuum-actuated wastegates and electronic control valves – an integrated charge air cooler system with low-volume air ducts and a 10.2:1 compression ratio.
When combined with a new high-performance paddle-shifted eight-speed automatic transmission – able to shift gears in 0.3 of a second on wide-open-throttle upshifts – the new engine helps the Cadillac CTS sedan reach 0-100km/h in an estimated 4.6 seconds and an estimated top speed of 274km/h.
The new twin-turbo V6 will power the Cadillac CTS and XTS, once launched in the US towards the end of the year, with the new CTS also to be offered with a 239kW/373Nm naturally aspirated 3.6-litre V6 and a 203kW/400Nm 2.0-litre turbocharged four-cylinder.
While the new high-performance V6 is good news for GM customers in the US, it could also be good news locally if Holden were to incorporate the twin-turbo unit into its line-up via GM’s parts sharing arrangements and possibly the next Holden Commodore that is due in 2017.
GM vice president of global manufacturing and president of international operations Tim Lee told CarAdvice at the Detroit auto show in January that Holden could “absolutely” use the GM Alpha platform, the same global rear-wheel-drive architecture that underpins the new Commodore-sized Cadillac CTS, for its future model.
The 2013 New York auto show kicks off on March 27.