Cadillac begins a new chapter in its high-performance legacy with the introduction of the brand’s first-ever twin-turbo V-8 engine. Set to be available in the Middle East by 2019, the new engine will be the centerpiece of the new CT6 V-Sport, an engaging sports sedan infused with DNA of Cadillac’s world-renowned motorsports program.
Developed as a small-displacement V-8 in the classic vein and offering exceptional power density of 131 hp (98 kW) per liter, this new Cadillac-exclusive 4.2L Twin Turbo V-8 — GM estimated at 550 horsepower (410 kW) and 627 lb-ft of torque (850 Nm) — elevates the CT6’s performance to a new plateau and offers drivers an unparalleled experience behind the wheel. An optional 500-horsepower version will also be available.
“With the new and exclusive 4.2L Twin Turbo V-8, we present to our Middle East customers a new, higher level driving experience, one that’s even more exhilarating than what they usually expect to get from Cadillac,” said Christian Soemmer, Managing Director, Cadillac Middle East. “Since the launch of our first V-series model in the region, we have received great feedback from our customers, confirming their interest in high-performance cars and felt their enthusiasm for a high-adrenaline driving experience which embodies Cadillac performance on and off the racetrack.”
The new Cadillac Twin Turbo V-8 is a clean-sheet design that also introduces unique design elements developed to balance performance and efficiency with compact, mass-efficient packaging.
At the center of the 4.2L Twin Turbo V-8 is a “hot V” configuration that transposes the conventional layout of the cylinder heads’ intake and exhaust systems to mount the turbochargers at the top of the engine to virtually eliminate turbo lag and reduce the engine’s overall packaging size.
The new engine’s foundation is an all-new, durable and lightweight aluminum cylinder block that houses an equally robust, lightweight rotating assembly composed of a forged steel crankshaft, forged steel connecting rods and high-strength aluminum pistons.
Its comparatively small-bore dimension enables the reduction in the size and weight of the pistons, optimizing the engine’s geometry to match the fast-rev capability permitted by the engine’s low-inertia, twin-scroll turbochargers. The result is exceptional responsiveness and immediacy of power across the rpm band.
The turbos’ twin-scroll design broadens their performance capability, offering quicker response and greater efficiency. The twin-scroll design has a divided housing with two exhaust gas inlets and two nozzles to drive the turbine. Generally, one of the nozzles contributes to quicker response and boost production, while the other contributes to overall peak performance.
Each of the engine’s integrated exhaust manifolds/turbocharger housings splits the exhaust channels from the cylinder head so the exhaust flows through separate scrolls based on the engine’s exhaust pulses. When matched with precise valve timing, that separation leverages exhaust-scavenging techniques to optimize gas flow, improves turbine efficiency and reduces turbo lag.
An efficient water-to-air charge-cooling system contributes to the engine’s performance, enhancing the turbochargers’ effectiveness, through an optimal combustion and more power.
The new Cadillac Twin Turbo V-8 is matched with a 10-speed automatic transmission. Its wide, 7.39 overall gear ratio spread enhances off-the-line performance and contributes to reduced engine speed on the highway, which enhances refinement and efficiency. Smaller steps between the gears also help the engine maintain the optimal speed for maximum power at almost all vehicle speeds.