Chevrolet Gemini small-block engine
| Gemini small-block engine | |
|---|---|
| Overview | |
| Manufacturer | General Motors (Chevrolet) | 
| Production | 2022–present | 
| Layout | |
| Configuration | 90° V8 | 
| Displacement | 5,463 cc (333.4 cu in) | 
| Cylinder bore | 104.25 mm (4.104 in) | 
| Piston stroke | 80 mm (3.1 in) | 
| Cylinder block material | Sand-cast A319 Aluminum | 
| Cylinder head material | Aluminum | 
| Valvetrain | DOHC 4 valves | 
| Compression ratio | 
 | 
| RPM range | |
| Max. engine speed | 8,600 RPM (soft), 9,000 RPM (hard) | 
| Combustion | |
| Turbocharger | Twin-turbo (LT7) | 
| Fuel system | 
 | 
| Management | GM E68 (32-bit) | 
| Fuel type | Gasoline | 
| Oil system | Dry sump | 
| Cooling system | Water-cooled | 
The Chevrolet Gemini small-block engine is a dual-overhead cam (DOHC) V8 engine designed by General Motors. While technically a small-block engine because of its bore spacing of 4.4 inches, General Motors engineers do not consider it to be a part of the traditional Chevrolet small block lineage because of the substantial reworking, specialized development, and unique technical features distinguishing its design.
The Gemini is a clean-sheet design, mechanically unrelated to both the LS-based engines and the Cadillac Blackwing V8. Its most notable traits include a flat-plane crankshaft and dual-overhead camshafts, which represents a departure from the traditional pushrod valves and crossplane crankshafts found in all previous generations of Chevrolet small-block engines. As of July 2024, the Gemini engine has two variants, dubbed LT6 and LT7.