Cadillac twin-turbo V8
The Cadillac Blackwing V8 (GM RPO LTA) is a twin-turbo DOHC V8 engine produced by General Motors for use in Cadillac vehicles only. It is a clean sheet engine design, as well as Cadillac's first ever twin-turbo V8 engine. The engine was branded as the "Blackwing V8" by GM technicians, and is the first Cadillac-exclusive dual overhead cam V8 engine since the Northstar V8 was dropped in 2011.[1]
| Cadillac Blackwing V8 | |
|---|---|
| Overview | |
| Manufacturer | General Motors |
| Also called | LTA Blackwing |
| Production | 2019–present |
| Layout | |
| Configuration | 90° V8 |
| Displacement | 4.2 L; 255.8 cu in (4,192 cc) |
| Cylinder bore | 86 mm (3.39 in) |
| Piston stroke | 90.2 mm (3.55 in) |
| Block material | Aluminum |
| Head material | Aluminum |
| Valvetrain | DOHC 4 valves x cyl. |
| Compression ratio | 9.8:1 |
| Combustion | |
| Turbocharger | hot-V twin scroll Twin-turbos with intercoolers |
| Fuel system | Direct injection |
| Fuel type | Gasoline |
| Cooling system | Water-cooled |
| Output | |
| Power output | 500–550 hp (373–410 kW) |
| Specific power | 131.2 hp (97.8 kW) per liter |
| Torque output | 574–640 lb⋅ft (778–868 N⋅m) |
| Chronology | |
| Predecessor | Cadillac Northstar engine |
The aluminum cylinder block features pressed-in iron liners, cross-bolted main bearing caps and houses a lightweight rotating assembly composed of a forged steel crankshaft, forged steel connecting rods and high strength hypereutectic aluminum pistons. Its firing order is 1-5-4-3-6-8-7-2.
The aluminum cylinder heads house dual overhead camshafts and four valves per cylinder; exhaust valves are sodium-filled.
The turbochargers are mounted between the cylinder banks in a so-called hot-V configuration and their twin scroll design broadens their performance capability, offering quicker response and greater efficiency. The turbochargers produce up to 20 psi (1.4 bar) and are matched with electronic wastegate control for more precise boost management and more responsive torque production. Ninety percent of the engine's peak torque is available at 2000 rpm and carried through 5200 rpm.
The engine features the following highlight characteristics:
- Twin-scroll turbochargers
- Electronic wastegate control
- Dual water-to-air charge coolers
- Dual electronic throttle bodies
- Direct injection
- Dual-independent camshaft phasing
- Active Fuel Management / Cylinder Deactivation
- Variable-pressure oiling system with piston-cooling oil jets
- Stop/start technology
All versions are currently slated to be equipped with the 10L90 10-speed automatic transmission and Cadillac's all-wheel drive system.
Versions
| Years | Model | Power | Torque |
|---|---|---|---|
| 2019–present | Cadillac CT6 Platinum and Cadillac CT6-V | 500–550 hp (373–410 kW) @ 5,700 rpm | 574–640 lb⋅ft (778–868 N⋅m) @ 3,200-4,000 rpm |