Mercedes‑AMG M139 2.0 L Turbo‑Hybrid
The W206 C63 AMG S E‑Performance uses a 2.0‑litre M139 four‑cylinder that makes 469 hp and 402 lb‑ft. With a 4.8 kWh battery and rear electric motor the system reaches 671 hp and 752 lb‑ft, delivering an astonishing 335.5 hp per litre when hybridized.
- Displacement: 2.0 L
- Engine output: 469 hp (235 hp/L)
- Hybrid system output: 671 hp (335.5 hp/L)
- Torque: 752 lb‑ft
Volvo XC60 T8 2.0 L Supercharged‑Turbo Hybrid
The XC60 T8’s 2.0‑litre inline‑four produces 328 hp on its own (164 hp/L). Adding an 11.6 kWh battery and electric motor lifts total output to 415 hp, or 207.5 hp per litre, while still achieving 26‑28 MPG combined.
- Displacement: 2.0 L
- Engine output: 328 hp (164 hp/L)
- Hybrid system output: 415 hp (207.5 hp/L)
- Torque: 494 lb‑ft
Porsche 911 GT2 RS 3.8 L Twin‑Turbo Flat‑Six
The track‑focused GT2 RS is powered by a 3.8‑litre boxer‑six that delivers 690 hp and 553 lb‑ft, equating to 182 hp per litre. No hybrid assistance is used, yet the output rivals many larger V8s.
- Displacement: 3.8 L
- Engine output: 690 hp (182 hp/L)
- Torque: 553 lb‑ft
- Future hybrid version: projected 750 hp total
Ferrari F80 3.0 L Twin‑Turbo V6 Hybrid
Ferrari’s upcoming F80 hypercar features a 3.0‑litre 120‑degree V6 that makes 888 hp (296 hp/L). Coupled with electric motors and a 2.28 kWh pack, the combined system reaches 1,184 hp, or 394 hp per litre—the highest ratio of any production car to date.
- Displacement: 3.0 L
- Engine output: 888 hp (296 hp/L)
- Hybrid system output: 1,184 hp (394 hp/L)
- Torque: 627 lb‑ft
- Limited production: 799 units