Cadillac's new twin-turbo V-6 is the most powerful engine of its type ever at GM.
It could be a critical year for Cadillac, the U.S. luxury maker hoping to take European competitors like BMW down a peg with an assortment of new products – and a new twin-turbo V-6 powertrain that it will be introducing later this year.
The all-new engine will make its debut under the hood of the third-generation Cadillac CTS that’s also scheduled to be unveiled at the New York Auto Show later this month. A first for General Motors, the twin-turbo V-6 “will be a signature feature” for the Cadillac brand, proclaimed David Leone, the maker’s executive chief engineer, during a Monday morning preview.
The CTS itself will undergo some major changes for the 2014 model-year, the sedan expected to grow slightly larger to create some distance from Cadillac’s base model, the ATS, and to more directly target imports like the vaunted BMW 5-Series, Audi A6 and Mercedes-Benz E-Class.
Cadillac plans to offer three different powertrains for the 2014 CTS, including a 2.0-liter single-turbo inline-four, a 3.6-liter naturally aspirated V-6, and the new twin-turbo, which will also displace 3.6 liters.
But the two sixes have very little in common, Cadillac engineers updating virtually every component in the newer powertrain. Once final numbers are confirmed, Leone expects it will produce 420 horsepower and 430 pound-feet of torque, compared to 321 hp and 275 lb-ft for the conventional V-6.
On the technical side, GM has developed a unique intercooler that not only allows it to increase turbo boost but significantly reduces the familiar turbo lag that plagues so many other turbocharged models. That’s because the intercooling system is mounted atop the engine, reducing the amount of compressed air the turbos have to pump before it flows into the engine.
For the tech-savvy, the new turbos deliver a full 12 psi of boost, while the compression ratio of the engine itself has been bumped to 10.2:1. An “onboard weather station” is designed to adjust engine operations depending upon factors such as temperature and barometric pressure and can even increase boost substantially to compensate for when the vehicle is being operated at high altitudes.
The new twin turbo packages will be directly targeted at the 4.4-liter BMW V-8 which produces 400 hp and 450 lb-ft of torque. Cadillac’s engine is about 40 pounds lighter which, the maker claims, should give it an additional advantage.
According to Leone, the new engine should be able to propel the new CTS from 0 to 60 in “under 5.0 seconds.”
In the new sedan, it will be paired with an all-new 8-speed automatic transmission. The new ATS will be offered in rear-wheel-drive, though an all-wheel-drive package is also anticipated.
But the twin-turbo also will be used in the Cadillac XTS where it will be mated to a 6-speed gearbox. The XTS uses a transverse engine layout and can be ordered in either front or all-wheel-drive. In the XTS, the engine will be downrated to 410 hp and 370 lb-ft.
Cadillac officials are remaining mum about specific details with the third-generation CTS but the new sedan is expected to be larger than the current model, which is often referred to as a “tweener,” sized somewhere between BMW’s 3- and 5-Series models.
The twin-turbo will likely not remain the most powerful engine package in the CTS line for long, however. Cadillac is expected to eventually add an even more high-performance powertrain for the next-gen V-Series version. It remains to be seen if the next CTS-V will follow previous form and go with a V-8 or opt for a smaller displacement V-6 alternative.
Meanwhile, Leone hints that the twin-turbo “could” find another application in the smaller ATS sedan, possibly powering its long-anticipated V-Series version. More details about the ATS-V could be released later this year.