McLaren M838T vs M840T Engines

McLaren M838T vs M840T Engines

The McLaren M840T engine is an evolution of the M838T. The M840T, debuting in the 720S, is a 4.0-liter twin-turbocharged V8, while the M838T is a 3.8-liter. The M840T features a longer stroke, new twin-scroll turbochargers, and a redesigned cooling system, among other changes. 

Here’s a more detailed breakdown:

M838T:
  • 3.8-liter twin-turbocharged V8 engine.
  • Used in models like the MP4-12C, 650S, and 675LT.
  • Developed with input from Ricardo, British engineering specialists.
  • Also used in the McLaren P1, with modifications for hybrid integration. 
M840T:
  • 4.0-liter twin-turbocharged V8 engine.
  • Debuted in the McLaren 720S.
  • A significant evolution of the M838T.
  • Features a longer stroke (3.6mm longer than the M838T).
  • New twin-scroll turbochargers with low inertia titanium-aluminium turbines.
  • Actively controlled wastegates for optimal efficiency.
  • 41% of components are new compared to the M838T.
  • Improved cooling and stronger internal components.
  • Engine control software updates.
  • More powerful, efficient, and responsive than the M838T.