Russian research institute NAMIs has developed the NA-4123-300, a 300-horsepower V8 gasoline engine tailored for high-speed planing boats weighing up to 3 tons. Based on the 4.4-liter V8 powering Aurus luxury cars, this marine engine targets a segment long dominated by foreign brands like Yamaha, Mercury, and Volvo Penta.
The automotive version of this 4.4-liter twin-turbo V8 delivers 598 hp and 880 Nm of torque. For marine use, NAMIs stripped it down considerably-dropping the turbochargers to rely on a naturally aspirated intake. This simplification fits the needs of recreational boat owners who prioritize reliability over peak racing performance.
NAMIs also redesigned the cooling and exhaust systems for marine conditions. The engine uses a dual-circuit cooling setup: coolant circulates internally, while seawater flows through an external loop. The exhaust is water-cooled and routed through an angled drive unit. Thrust is transmitted via a Russian-made angled outdrive unit, replacing imported components.
NA-4123-300 marine engine specifications
- Engine type: Gasoline V8
- Displacement: 4.4 liters
- Power output: 300 hp
- Intended use: Planing boats up to 3 tons
- Cooling system: Dual-circuit with seawater cooling
- Drive: Angled outdrive unit by Russian partner
For decades, the 300-hp boat engine segment in Russia has been dominated by imports such as the Yamaha F300 and Mercury Verado 300. Since 2022, international supply chains to Russia’s small craft sector have tightened dramatically, with official channels disrupted and occasional parallel imports failing to cover demand. Against this backdrop, NAMIs’s domestic engine and outdrive combo presents a pragmatic attempt to fill the void with a homegrown alternative, rather than just a proof-of-concept.
The project’s success now hinges on production timelines, serial manufacturing, and reliable after-sales service – critical factors for boat owners who require seasonal repairs, spare parts availability, and a clear estimate of engine lifespan. If NAMIs manages to bring this engine fully to market, it would mark a rare expansion of the Aurus platform beyond automobiles into marine propulsion.