Cadillac once again leads GM's technology efforts, this time with a new drivetrain for its 2014 CTS model. One of this new model's three engine choices will be a direct-injection 3.6-liter V-6, producing 420 horsepower.
The current CTS comes with either a 3-liter or 3.6-liter V-6, both featuring direct injection, outputting 270 horsepower and 318 horsepower respectively. The new CTS comes out with the twin turbo, a revised nonturbo 3.6-liter V-6, and a 2-liter four-cylinder using direct injection and a turbo to produce 272 horsepower.
The danger of using a turbocharger to boost power is turbo lag, uneven acceleration caused by the time it takes the turbo to kick in. Cadillac says that 90 percent of the new engine's 430 pound-feet of torque is available from 2,500rpm to 5,500rpm, which should mean very little lag.
Cadillac used two low-pressure turbos, one for each bank of cylinders, on the new engine, allowing them to spin up faster. The company also fitted the turbos with electronic vacuum-actuated recirculation valves to control the waste gates, a system designed to deliver better control over the turbo performance.
Cadillac estimates that the new twin-turbo-powered CTS will hit 60 mph in 4.6 seconds, and have a top speed of 170 mph.
Complementing the new engine will be an eight-speed automatic transmission. Its electronic controls will let it skip gears when downshifting or upshifting for quicker changes. Drivers will be able to manually select gears as well, and a lockup torque converter will lead to tighter shifts.
Most importantly, the engine and transmission combination should get the CTS an EPA mileage rating of 17 mpg city and 25 mpg highway. Cadillac estimates the 2-liter turbocharged CTS at 19 mpg city and 30 mpg highway.
The 2014 CTS will be unveiled next week at the New York International Auto Show.