The Polestar B6304T2 is a 2,951 cc, inline‑six turbocharged petrol engine produced between 2020 and 2024. It features a twin‑scroll turbocharger, direct fuel injection, and dual overhead camshafts (DOHC), delivering outputs ranging from 310 kW (420 PS) to 335 kW (455 PS) with torque figures between 660–740 Nm. The twin‑scroll turbocharger minimizes lag for immediate throttle response.
Fitted exclusively to the Polestar 1, this engine was engineered as part of a plug‑…
Production years 2020–2024 meet Euro 6d-TEMP standards .
The Polestar B6304T2 is a 2,951 cc inline‑six turbocharged petrol hybrid engine engineered for the Polestar 1 grand tourer (2020-2024). It combines direct injection with a twin‑scroll turbocharger to deliver immense, linear power and torque. Designed to meet Euro 6d-TEMP standards, it forms the combustion component of a sophisticated plug-in hybrid system.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,951 cc | |
Fuel type | Petrol | |
Configuration | Inline‑6, DOHC, 24‑valve | |
Aspiration | Twin‑scroll turbocharged | |
Bore × stroke | 82.0 mm × 93.0 mm | |
Power output | 310–335 kW (420–455 PS) | |
Torque | 660–740 Nm @ 2,200–5,400 rpm | |
Fuel system | High-pressure direct injection (Bosch HDEV6) | |
Emissions standard | Euro 6d-TEMP | |
Compression ratio | 10.5:1 | |
Cooling system | Water‑cooled | |
Turbocharger | Single twin‑scroll unit (BorgWarner) | |
Timing system | Chain-driven | |
Oil type | Refer to vehicle handbook / manufacturer specification | |
Dry weight | 215 kg |
The Polestar B6304T2 was used exclusively in the Polestar 1 with longitudinal mounting. This engine, derived from Volvo's B6304T family, received specific adaptations for the Polestar 1's hybrid system-including a unique engine control unit and integration with the rear electric motors. All adaptations are documented in OEM technical bulletins.
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The B6304T2's primary reliability consideration is potential oil consumption under aggressive driving, documented in early production units. Polestar SIB PSB-2022-08 outlines the condition, while owner reports suggest it is manageable with vigilant monitoring. Sustained high-RPM operation makes regular oil level checks critical.
Analysis derived from manufacturer technical service bulletins and industry workshop records. Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The B6304T2 is a robust, well-engineered engine derived from Volvo's proven units. Its main consideration is potential oil consumption under hard use, which Polestar addressed with a service bulletin. With regular oil checks, use of correct 0W-20 oil, and adherence to service schedules, it should prove very reliable for the long term.
The most documented issues are potential oil consumption (addressed by Polestar), GPF clogging from short trips, and occasional turbo wastegate rattle on cold starts. Intake manifold runner faults are also reported. These are covered in Polestar service bulletins and owner advisories.
The B6304T2 engine was used exclusively in the Polestar 1 plug-in hybrid grand tourer, produced from 2020 to 2024. It is not found in any other Polestar or Volvo model, making it unique to this limited-production vehicle.
Aftermarket ECU tuning is common on the B6304T2 platform, but increasing boost or altering engine parameters accelerates component wear, impacts emissions compliance, and may void vehicle warranties. Any modifications should be evaluated carefully by a qualified specialist.
Official figures are complex due to its hybrid nature. On pure petrol, expect ~10.5 L/100km (27 mpg UK) combined. With regular charging and mixed driving, overall consumption can drop significantly, with many owners reporting 50-100 mpg UK equivalent depending on electric usage.
Yes. Like virtually all modern DOHC engines, the B6304T2 is an interference design. If the timing chain were to fail, valve and piston contact would cause catastrophic internal damage. Thankfully, the chain system is very robust and not a known failure point.
It requires Polestar/Volvo specification VCC RBS0-2AE, which is a 0W-20 synthetic oil. Using the correct low-viscosity oil is crucial for protecting the turbocharger, ensuring proper chain lubrication, and maintaining fuel efficiency. Never use a thicker oil.
Comprehensive technical documentation and regulatory references
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UK vehicle approval processes, import rules, and MoT guidance.
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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