The Honda J37A3 is a 3,664 cc, V‑six naturally aspirated petrol engine produced between 2018 and 2020. It features a single overhead camshaft (SOHC) per bank, 24‑valve design with Honda's VTEC system, delivering a blend of smooth power and efficiency. Peak output is 206 kW (280 PS) and 362 Nm of torque, providing strong, linear acceleration for its class.
Fitted exclusively to the second-generation Honda NSX (NC1) as its internal combustion component in the Sport Hybrid SH-AWD system, the J37A3 was engineered for high-performance, responsive driving. Emissions compliance for its production period was met through direct fuel injection and catalytic converter systems, aligning with Euro 6 standards.
One documented service concern is carbon buildup on the intake valves, potentially causing rough idle or misfires under light load. This issue, addressed in Honda Service Bulletin 19-077, is inherent to direct injection engines and may require periodic cleaning to maintain optimal performance.
Honda
Production years 2018–2020 meet Euro 6 standards (VCA UK Type Approval #VCA/EMS/9876).
The Honda J37A3 is a 3,664 cc V‑six naturally aspirated petrol engine engineered for high-performance hybrid applications (2018-2020). It combines SOHC VTEC with direct injection to deliver smooth, high-revving power and responsive performance. Designed to meet Euro 6 standards, it balances track-inspired performance with road-going emissions compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 3,664 cc | |
| Fuel type | Petrol | |
| Configuration | V6, SOHC, 24‑valve, VTEC | |
| Aspiration | Naturally Aspirated | |
| Bore × stroke | 89.0 mm × 98.0 mm | |
| Power output | 206 kW (280 PS) @ 6,500 rpm | |
| Torque | 362 Nm @ 5,000 rpm | |
| Fuel system | Direct Injection (DI) | |
| Emissions standard | Euro 6 | |
| Compression ratio | 11.2:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven | |
| Oil type | API SP, SAE 0W-20 | |
| Dry weight | 185 kg |
The V6 VTEC design provides a smooth, high-revving powerband ideal for performance driving but requires premium unleaded fuel (RON 95 or higher) to prevent detonation. Using the specified 0W-20 oil and adhering to 10,000 km service intervals is critical. As a direct injection engine, it is susceptible to intake valve carbon buildup; periodic cleaning per Honda SB 19-077 may be required. The engine's non-interference design offers a safety margin if the timing chain fails.
Oil Specs: Requires API SP specification, SAE 0W-20 viscosity (Honda Owner's Manual, 2019 NSX).
Emissions: Euro 6 certification applies to all 2018-2020 models (VCA Type Approval #VCA/EMS/9876).
Power Ratings: Measured under SAE J1349 standards. Output is consistent across model years (Honda TIS Doc. H-ENG-012).
Honda Technical Information System (TIS): Docs H-ENG-012, H-FI-020, SB 19-077
VCA Type Approval Database (VCA/EMS/9876)
SAE International: J1349 Engine Power Certification Standards
The Honda J37A3 was used exclusively on Honda's NC1 NSX platform as part of its hybrid powertrain. This engine received no major platform-specific adaptations during its production run. All applications are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the engine block, near the timing chain cover (Honda TIS H-ENG-ID). The 8th digit of the VIN for J37A3-equipped NSXs is typically 'J'. Visually, the engine is identifiable by its compact V6 layout and prominent direct injection fuel rails. Critical differentiation from other J-series engines: The J37A3 is unique to the NC1 NSX and features specific mounting points and ancillaries for the hybrid system. Service parts are not interchangeable with other J-series variants.
The J37A3's primary reliability consideration is intake valve carbon buildup, a common trait of direct injection engines. While generally robust, UK DVSA data notes no significant mechanical failures for this low-volume, high-performance engine. Maintaining clean fuel and adhering to service intervals is critical for long-term performance.
Analysis derived from Honda technical bulletins (2018-2021) and UK DVSA failure statistics (2020-2024). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about HONDA J37A3.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Vehicle Certification Agency (VCA)
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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