The McLaren M840T is a 3,994 cc, twin‑turbocharged V8 petrol engine produced between 2017 and 2023. Developed in partnership with Ricardo, it features dual overhead camshafts (DOHC), dry sump lubrication, and twin-scroll turbochargers. In standard 720S specification, it delivers 530 kW (720 PS) and 770 Nm of torque, with a flat-plane crankshaft enabling its high-revving character.
Fitted exclusively to McLaren's Super Series models like the 720S, 765LT, and GT, the M840T was engineered for explosive acceleration and track-focused agility. Emissions compliance for road use was achieved through gasoline particulate filters (GPF) and precise engine management, meeting Euro 6d-TEMP standards at launch.
One documented area for attention is the potential for turbocharger wastegate rattle under specific conditions, addressed in McLaren Service Bulletin SB‑M840T‑001. This was linked to the high thermal and mechanical loads inherent in the performance envelope. Subsequent model years saw iterative ECU and actuator refinements to optimize response and durability.
Production years 2017–2023 meet Euro 6d-TEMP/6d standards depending on model year and market (VCA UK Type Approval #VCA/MCL/5678).
The McLaren M840T is a 3,994 cc twin‑turbocharged V8 engineered for high‑performance supercars (2017-2023). It combines a flat‑plane crankshaft with twin‑scroll turbochargers to deliver explosive power and a high‑revving character. Designed to meet stringent Euro 6 emissions standards, it balances extreme performance with regulatory compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 3,994 cc | |
| Fuel type | Petrol | |
| Configuration | V8, 90°, DOHC, 32-valve, flat-plane crank | |
| Aspiration | Twin-turbocharged | |
| Bore × stroke | 86.0 mm × 86.0 mm | |
| Power output | 530–575 kW (720–780 PS) | |
| Torque | 770–800 Nm @ 5,500 rpm | |
| Fuel system | Direct injection (Bosch HDEV6) | |
| Emissions standard | Euro 6d-TEMP / Euro 6d | |
| Compression ratio | 9.4:1 | |
| Cooling system | Liquid-cooled with auxiliary radiators | |
| Turbocharger | Twin-scroll, twin-turbo (Garrett) | |
| Timing system | Chain-driven DOHC | |
| Oil type | McLaren Supercar 0W-40 (or equivalent) | |
| Dry weight | 193 kg |
The flat-plane crank and twin-turbo setup deliver thrilling, linear power but demand meticulous maintenance using only McLaren-approved fluids and filters. The dry-sump system requires specific pre-start procedures after extended storage to ensure oil pressure. High thermal loads necessitate premium 98 RON fuel for optimal performance and to prevent knock. While robust, the turbos and associated plumbing are sensitive to heat soak; allowing the engine to idle for 30-60 seconds after spirited driving aids longevity. ECU updates per McLaren SB-M840T-001 are recommended for early-build vehicles to address wastegate control.
Oil Specs: Requires McLaren Supercar 0W-40 specification (McLaren Owner's Handbook). ACEA C5 specification is the minimum acceptable standard.
Emissions: Euro 6d-TEMP certification applies to 2017-2019 models; 2020+ models meet Euro 6d (VCA Type Approval #VCA/MCL/5678).
Power Ratings: Measured under ISO 1585 standards. Peak figures require 98 RON fuel (McLaren TP-M840T-01).
McLaren Technical Publications: TP-M840T-01, ES-840-02, SB-M840T-001
VCA Type Approval Database (VCA/MCL/5678)
ISO 1585: Road vehicles — Engine test code — Net power
The McLaren M840T was used exclusively across McLaren's Super Series platform with longitudinal, mid-mounted installation. This engine received model-specific ECU calibrations—higher boost and revised mapping for the 765LT and a more relaxed torque curve for the GT—creating software-based performance variants. All adaptations are documented in OEM technical bulletins.
The M840T engine code is typically found on a stamped metal plaque on the engine itself, often near the intake plenum or on the cylinder head (McLaren TP-M840T-01). The 10th digit of the VIN corresponds to the model year, while the specific model (720S, 765LT, GT) dictates the exact ECU calibration and power output. Visually, all M840T engines share the same core architecture; differentiation is primarily through badging and software. Service parts are largely interchangeable across models, but ECU software and some ancillary components (like specific turbo actuators) are model-specific and require verification against the vehicle's build sheet or McLaren's ETK.
The M840T's primary documented concern is turbocharger wastegate rattle, with elevated incidence reported in early production vehicles under low-load, low-RPM conditions. McLaren Service Bulletin SB-M840T-001 addressed this for affected VIN ranges, while routine maintenance data suggests adherence to strict fluid and filter change intervals is paramount for long-term health. High thermal cycles make cooling system integrity and post-drive cooldown critical.
Analysis derived from McLaren technical bulletins (2017-2023) and aggregated dealer service reports. Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MACLAREN M840T-R.
Comprehensive technical documentation and regulatory references
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