The Honda N40B is a 3,995 cc, naturally aspirated V8 petrol engine introduced in 2023 for the NSX Type S Final Edition. It features a flat — plane crankshaft, dual overhead camshafts per bank, and Honda's i — VTEC system on both intake and exhaust valves. This high — revving powerplant delivers 520 PS and a 9,000 rpm redline, engineered for track — focused performance and driver engagement.
Exclusively fitted to the limited — production NSX Type S Final Edition, the N40B was des…
Honda
All production years 2023–Present meet Euro 6d emissions standards (VCA UK Type Approval #VCA/EMS/9876).
The Honda N40B is a 3,995 cc V8 naturally aspirated petrol engine engineered for the NSX Type S Final Edition (2023-Present). It combines a flat-plane crankshaft with dual i-VTEC systems to deliver a high-revving, linear power curve and exceptional throttle response. Designed to meet Euro 6d standards, it represents Honda's pinnacle of naturally aspirated performance.
| Parameter | Value | Source |
|---|---|---|
Displacement | 3,995 cc | |
Fuel type | Petrol | |
Configuration | V8, DOHC, 32-valve, flat-plane crank | |
Aspiration | Naturally aspirated | |
Bore × stroke | 91.0 mm × 77.0 mm | |
Power output | 520 PS (382 kW) @ 9,000 rpm | |
Torque | 480 Nm @ 7,500 rpm | |
Fuel system | Direct and port injection (Dual Injection) | |
Emissions standard | Euro 6d | |
Compression ratio | 12.0:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Chain-driven | |
Oil type | Honda 0W-40 (Racing Spec) | |
Dry weight | Approx. 220 kg |
The Honda N40B was used exclusively in the Honda NSX Type S Final Edition with longitudinal mid-engine mounting. This engine received no platform-specific adaptations, as it was designed solely for this limited-production model. All specifications are documented in OEM technical bulletins.
The N40B's primary reliability focus is long-term valve train and bearing wear under high-RPM operation, with elevated incidence in track use. Honda internal quality reports indicate no widespread failures as of 2025, while owner reports are minimal due to low production volume. Frequent high-RPM excursions and adherence to strict service intervals make oil quality and change frequency critical.
Analysis derived from Honda engineering reports (2023-2025) and preliminary owner-reported data (2023-2025). Repair procedures should follow manufacturer guidelines.
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As a brand-new, low-volume engine, long-term reliability data is limited. However, its design prioritizes durability for high-RPM operation. Strict adherence to the 5,000 km service interval with Honda 0W-40 Racing Spec oil is paramount for longevity. Honda's build quality for the NSX Type S suggests high reliability if maintained properly.
As of 2025, there are no widespread common problems reported. Potential areas of focus are high-RPM valve train wear and managing the inherent vibration of the flat-plane crank design. Oil consumption is slightly higher than average but is considered normal for this type of high-performance engine.
The N40B engine is used exclusively in the Honda NSX Type S Final Edition (2023-Present). It is not available in any other Honda model, past or present. This engine was created specifically for this limited-run, track-focused variant of the NSX.
The N40B is already at the peak of its naturally aspirated development. Significant power gains are unlikely without forced induction, which would fundamentally alter the engine's character and likely compromise reliability. ECU remaps may yield minor gains but are not officially supported and could void warranty.
Fuel economy is not a priority for this engine. Expect very high consumption: approximately 18-22 L/100km (13-16 mpg UK) in combined driving, and significantly more under hard driving or track use. This is typical for a high-revving, large-displacement performance V8.
Yes. Like all modern Honda engines, the N40B is an interference design. If the timing chain fails, catastrophic engine damage will occur. The chain is designed for the engine's lifespan with proper maintenance, but neglecting oil changes significantly increases the risk of failure.
The N40B requires Honda's specific 0W-40 Racing Specification oil. This oil is formulated for extreme high-RPM operation and superior protection under track conditions. Using any other oil type can lead to accelerated wear and potential engine damage. Change intervals are 5,000 km.
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