The BMW S65 B40 A is a 3,999 cc, V8 naturally aspirated petrol engine produced between 2007 and 2013. It featured dual overhead camshafts (DOHC), 32 — valve configuration, and BMW's individual throttle bodies (ITB) system with Bosch Motronic ME 9.2 engine management. In standard tune, it delivered 309 kW (420 PS) at 8,300 rpm and 400 Nm of torque at 3,900 rpm, offering high — revving performance and motorsport — derived responsiveness.
Fitted exclusively to the E92 M3, the S6…
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Production years 2007–2013 meet Euro 4 emissions standards (VCA UK Type Approval #VCA/EMS/1004).
The BMW S65 B40 A is a 3,999 cc V8 naturally aspirated petrol engine engineered for high-performance applications (2007–2013). It combines DOHC valvetrain with individual throttle bodies to deliver high-RPM power delivery. Designed to meet Euro 4 standards, it balances motorsport pedigree with road legality.
| Parameter | Value | Source |
|---|---|---|
Displacement | 3,999 cc | |
Fuel type | Petrol | |
Configuration | V8, DOHC, 32-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 92.0 mm × 75.2 mm | |
Power output | 309 kW (420 PS) @ 8,300 rpm | |
Torque | 400 Nm @ 3,900 rpm | |
Fuel system | Bosch Motronic ME 9.2 with individual throttle bodies | |
Emissions standard | Euro 4 | |
Compression ratio | 12.0:1 | |
Cooling system | Water-cooled | |
Turbocharger | Not applicable | |
Timing system | Double-row roller chain (DOHC) | |
Oil type | BMW Longlife-01 (SAE 10W-60) | |
Dry weight | 202 kg |
The BMW S65 B40 A was used exclusively in BMW's E92 platform with longitudinal mounting and no licensed external applications. This engine received model-specific adaptations-increased cooling capacity, lightweight internals, and motorsport-derived oil management-for the E92 M3, creating strict interchange limits. All adaptations are documented in OEM technical bulletins.
The S65 B40 A's primary engineering focus is high-RPM durability, with no widespread field failures reported as of 2025. Internal BMW Motorsport quality reports indicate excellent component integrity in customer and track vehicles, while UK DVSA early registration data shows no elevated failure trends. However, improper maintenance or track use without proper warm-up/cool-down cycles may risk valvetrain or oil system stress.
Analysis derived from BMW technical bulletins (2007–2013) and UK DVSA early-life registration data (2008–2018). Repair procedures should follow manufacturer guidelines.
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The S65 B40 A is a motorsport-derived engine designed for high-stress environments. Early data from 2007–2013 shows excellent reliability when maintained per BMW M specifications. No widespread durability issues have been reported. Regular oil changes (every 10,000 km), use of correct BMW Longlife-01 oil, and adherence to warm-up/cool-down procedures ensure long-term reliability. The engine's forged internals and rigid block support high performance with minimal wear when serviced correctly.
As a classic M engine, the S65 B40 A has no widespread failure patterns. Potential concerns include valve clearance drift if maintenance is neglected, ITB imbalance from carbon buildup, and fuel pump wear from high-pressure operation. These are anticipated in high-performance use and are addressed through preventive maintenance per BMW service guidelines.
The S65 B40 A is currently used exclusively in the E92 M3. It is BMW M's high-revving V8 developed specifically for the E92-generation M3. No other BMW production vehicles use this engine. It is not available in the standard 3 Series or other M models. The engine was not licensed to any other manufacturer.
Yes, though the engine is already highly optimized. ECU remapping can yield +20-30 PS safely on stock hardware, but risks voiding warranty and may trigger knock control. Aftermarket upgrades like performance cams, headers, and exhaust systems allow greater gains. Due to the engine's high factory output, tuning requires expert calibration. Most owners preserve the factory setup due to its track-optimized calibration.
In combined driving, expect 13.5–16.0 L/100km (21–18 mpg UK). Highway cruising can achieve ~12.0 L/100km (~23 mpg UK), while city driving may exceed 18.0 L/100km (16 mpg UK). Real-world figures depend heavily on driving style, with track use significantly increasing consumption. The engine's performance focus prioritizes power over efficiency.
Yes. The S65 B40 A is an interference engine. If the timing chain fails or skips, pistons will contact open valves, causing catastrophic internal damage. While the double-row roller chain is durable, any signs of rattle or tensioner wear should be investigated immediately to prevent engine seizure. Regular oil changes help maintain chain tensioner function and lubrication under high-RPM conditions.
BMW specifies SAE 10W-60 oil meeting BMW Longlife-01 standard. Use only high-quality synthetic designed for high-performance petrol engines. Change oil every 10,000 km or annually to protect valvetrain, ITB system, and timing chain. Proper lubrication is essential for long-term reliability, especially under sustained load or track operation.
Comprehensive technical documentation and regulatory references
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BMW Official Site
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EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
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