Chevrolet Gemini small-block engine
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.
| Gemini small-block engine | |
|---|---|
| Overview | |
| Manufacturer | General Motors (Chevrolet) |
| Production | 2022–present |
| Layout | |
| Configuration | 90° V8 |
| Displacement |
|
| Cylinder bore |
|
| Piston stroke |
|
| Cylinder block material |
|
| Cylinder head material | Aluminum |
| Valvetrain | DOHC 4 valves |
| Compression ratio | 12.5:1 |
| RPM range | |
| Max. engine speed | 8,600 RPM (soft), 9,000 RPM (hard) |
| Combustion | |
| Fuel system | Direct fuel injection |
| Management | GM E68 (32-bit) |
| Fuel type | Gasoline |
| Oil system | Dry sump |
| Cooling system | Water-cooled |
The LT6 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 February 2024, the Gemini engine has only one variant, dubbed LT6. Hagerty, an American insurance company, reported in 2020 that a higher horsepower variant, the LT7, is expected to arrive in the 2024 model year.