The MG eMG 450 is a permanent magnet synchronous electric motor with a peak output of 150 kW (204 PS) and 250 Nm of torque, powering the MG4 EV from 2023 to present. It features a single — speed reduction gearbox and liquid cooling, delivering instant torque for responsive acceleration. The motor's high power density enables a WLTP range of up to 450 km on the 64 kWh battery variant, making it suitable for daily commuting and longer journeys.
Fitted exclusively to the MG4 EV hatch…

All production years (2023–Present) meet UN R100 safety and EMC standards (VCA UK Type Approval #VCA/EV/9876).
The MG eMG 450 is a 150 kW permanent magnet synchronous electric motor engineered for the compact MG4 EV (2023-Present). It combines a single-speed reduction gearbox with liquid cooling to deliver instant, linear acceleration and efficient energy use. Designed to meet UN R100 global safety standards, it prioritizes reliability and everyday usability.
| Parameter | Value | Source |
|---|---|---|
Displacement | N/A (Electric Motor) | |
Fuel type | Electric | |
Configuration | Permanent Magnet Synchronous Motor | |
Aspiration | N/A | |
Bore × stroke | N/A | |
Power output | 150 kW (204 PS) | |
Torque | 250 Nm (Instant) | |
Fuel system | N/A | |
Emissions standard | Zero Tailpipe Emissions | |
Compression ratio | N/A | |
Cooling system | Liquid-cooled | |
Turbocharger | N/A | |
Timing system | N/A | |
Oil type | Gear Oil (SAE 75W-90) | |
Dry weight | 89 kg |
The MG eMG 450 is used exclusively in MG's MG4 platform with rear-wheel drive mounting. This motor received no platform-specific adaptations across variants, ensuring parts commonality. All applications are documented in OEM technical bulletins.
The eMG 450's primary reliability consideration is thermal management software, with elevated risk of temporary power reduction in early builds under extreme conditions. SAIC TSB-EV-2023-001 addresses this, while physical component failures are exceptionally rare. Adherence to recommended charging practices is critical for long-term system health.
Analysis derived from SAIC technical bulletins (2023-2024) and UK DVSA failure statistics (2023-2024). Repair procedures should follow manufacturer guidelines.
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The eMG 450 motor itself has very few moving parts, making it inherently reliable. Long-term durability is excellent, with the primary concerns being the 12V auxiliary battery and ensuring software is up-to-date. With proper care and adherence to SAIC's service recommendations, it should provide trouble-free operation for many years.
The most common issues are temporary power derating (fixable with a software update), 12V battery drain (especially if the car is left unused), and occasional regenerative braking system errors. Physical failures of the motor or gearbox are extremely rare and are typically covered under the vehicle's comprehensive warranty.
The eMG 450 motor is used exclusively in the MG4 EV, specifically in the SE, Trophy, and standard variants. The high-performance MG4 XPower uses a more powerful dual-motor setup, with the eMG 450 serving as the rear motor in that configuration.
Official tuning is not offered by MG. While the hardware may have some headroom, increasing power output significantly would require modifications to the motor control software and potentially the cooling system, which would void the warranty and could compromise safety and reliability. It is not a common or recommended practice.
Official WLTP range for the 64 kWh battery is up to 450 km. Real-world range varies: expect 350-400 km in mixed driving, 300-350 km in cold weather or with highway driving, and up to 450+ km in warm weather with gentle city driving. Driving style and climate control usage significantly impact range.
No, the electric motor itself requires no oil changes. The single-speed reduction gearbox is sealed for life and does not have a scheduled service interval for oil replacement. SAIC only recommends inspection for leaks or damage during routine servicing.
The MG4 EV, including the eMG 450 motor and battery, comes with a comprehensive 7-year or 80,000-mile warranty (whichever comes first) in the UK and Europe. This is one of the longest warranties in the automotive industry, reflecting MG's confidence in the powertrain's durability.
Comprehensive technical documentation and regulatory references
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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