Triumph 2000, 2500 & 2.5Pi Fuel System

The Triumph 2000 series employed two distinct fuel delivery systems: twin SU carburettors on standard models, and Lucas mechanical fuel injection on the pioneering 2.5Pi. Britain's first fuel-injected production saloon arrived in 1969, offering 132bhp compared to the carburettor 2000's 90bhp. The Lucas PI system demands meticulous maintenance, with the metering unit requiring specialist knowledge for proper adjustment and optimal engine performance.

Carburettor Systems

The 2000 and 2500 models used HS6 SU carburettors featuring constant depression principles and oil-damped pistons. Correct mixture adjustment affects fuel economy and power delivery, whilst worn throttle spindles cause erratic idling. Carburettor servicing requires balancing between both units for smooth running across the rev range. Regular maintenance prevents the bore wash that glazes cylinder walls.

Fuel Injection Components

The 2.5Pi's Lucas system uses a mechanical fuel pump delivering fuel at precise pressures through the metering unit to individual injectors. The system's complexity means few specialists understand its proper adjustment, making correctly functioning components essential. Fuel tanks differ between saloon and estate variants. Adequate ignition timing remains critical for injection system performance. Browse our complete Triumph 2000 series range or explore performance upgrades.