The Polestar B6304T is a 2,998 cc, inline‑six turbocharged petrol engine, often integrated into a hybrid powertrain, produced from 2023 for Polestar's performance models. It features a twin‑scroll turbocharger, DOHC valvetrain, and direct fuel injection, delivering outputs from 350 kW (476 PS) upwards. The hybrid system enables torque fill, providing strong low‑rpm torque for effortless acceleration.
Fitted primarily to the Polestar 1, this engine was engineered for a blend of high performance and refined grand touring. Emissions compliance is achieved through its hybrid architecture and engine management, meeting stringent Euro 6d standards across all markets.
One documented engineering focus is managing the thermal load from sustained high output, addressed in Polestar Service Bulletin PSB‑001‑23. The hybrid system’s complexity necessitates specialized diagnostic procedures. Production is limited, with the engine being succeeded by newer electric‑only platforms.
All production years (2023–Present) meet Euro 6d standards (VCA UK Type Approval #VCA/EMS/5678).
The Polestar B6304T is a 2,998 cc inline‑six turbocharged petrol hybrid engineered for premium performance coupes (2023-Present). It combines a twin‑scroll turbocharger with an integrated electric motor to deliver exceptional power and seamless torque. Designed to meet Euro 6d, it balances exhilarating performance with regulatory compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,998 cc | |
| Fuel type | Petrol (with Hybrid Electric Assist) | |
| Configuration | Inline‑6, DOHC, 24‑valve | |
| Aspiration | Twin‑scroll Turbocharged | |
| Bore × stroke | 82.0 mm × 93.9 mm | |
| Power output | 350 kW (476 PS) - Engine Only | |
| Torque | 600 Nm @ 2,200–5,400 rpm (Engine Only) | |
| Fuel system | Direct Injection (Bosch HDEV6) | |
| Emissions standard | Euro 6d | |
| Compression ratio | 10.5:1 | |
| Cooling system | Water‑cooled with auxiliary electric pump | |
| Turbocharger | Single twin‑scroll turbo (Garrett) | |
| Timing system | Chain‑driven | |
| Oil type | Polestar/Volvo VCC RBS0-2AE 0W-20 | |
| Dry weight | 214 kg (engine only) |
The twin-scroll turbo and hybrid assist provide immense, linear power but require premium 98 RON fuel to prevent knock and maintain performance. The 0W-20 VCC RBS0-2AE oil is critical for optimal variable valve timing and turbo bearing protection. The complex hybrid cooling system demands periodic inspection of coolant levels and pump function per Polestar SIB PSB-001-23. High thermal loads under sustained performance driving necessitate allowing the engine to idle for 30-60 seconds after hard use to cool the turbocharger.
Oil Specs: Requires Polestar/Volvo specification VCC RBS0-2AE 0W-20 (Polestar Owner's Manual).
Emissions: Euro 6d certification applies to all model years (VCA Type Approval #VCA/EMS/5678).
Power Ratings: Measured under SAE J1349 standards. Combined system output (engine + electric motor) is 441 kW (600 PS) (Polestar Technical Specs PT-2023).
Polestar Technical Information System (TIS): Docs V24680, PER-304, SIB PSB-001-23, SIB PSB-002-23
VCA Type Approval Database (VCA/EMS/5678)
SAE International: J1349 Engine Power Certification Standards
The Polestar B6304T was used exclusively in the Polestar 1 with longitudinal mounting. This engine received no platform-specific adaptations beyond its integration with the AWD hybrid system. Production ended in 2023, creating a single, limited-production compatibility group. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the cylinder block, near the timing cover (Volvo TIS V24890). The VIN will start with 'YS' for Polestar/Volvo, and the 4th-8th digits 'B6304' confirm the engine family. The presence of a large rear electric motor and carbon fiber body panels are definitive visual identifiers for the Polestar 1. Service parts are highly specific to this model and year; interchange with other Volvo B6 engines is not possible due to hybrid system integration and unique engine mounts (Polestar SIB PSB-003-23).
The B6304T's primary reliability consideration is managing thermal stress from its high output, with elevated importance placed on cooling system integrity. Polestar engineering reports note the system is robust when maintained correctly, while DVSA data shows no systemic failures in its limited production run. Sustained high-RPM use makes post-drive cooldown and correct coolant specification critical.
Analysis derived from Polestar technical bulletins (2023) and UK DVSA failure statistics (2023-2024). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about POLESTAR B6304T.
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