BMW has boosted its 3 Series sedan and coupe line-ups by introducing a pair of new-generation six-cylinder engines.
Displacing 2.2 and 2.5 litres, the new M54 powerplants belong to the same family as the 3.0-litre unit that powers the recently introduced 330i and 330Ci.
The 2.2-litre unit powers the new 320i and 320Ci and generates 125kW - on par with the old 2.5-litre engine used in the defunct 323i.
This engine also powers the new Z3 2.2i roadster, which replaces the Z3 2.0. Somewhat surprisingly, the newcomer costs the same as its less potent predecessor - from $74,380.
The new 2.5-litre engine lurks under the bonnet of the 325i and 325Ci and cranks out 141kW - just 1kW less than the 2.8-litre unit that powered the outgoing 328i.
BMW says the M54 engines, which feature double-VANOS variable valve timing and 'fly-by-wire" throttle, are more responsive than their predecessors and cost less to maintain.
All six-cylinder engines offered in the 3 Series and Z3 are available with the Steptronic five-speed automatic transmission.
BMW has priced the 320i and 320Ci at $60,500 and $63,500 respectively, while the 325i and 325Ci cost $67,405 and $72,095 respectively The newcomers will bridge the gap between the 318i and 330i and enable the 3 Series to compete head-to-head with Mercedes-Benz's imminent new C-class.
The new C-class will also be offered with a choice of four petrol engines: normally aspirated and supercharged 2.0-litre four-cylinder units and 2.6 and 3.2-litre V6s.
BMW says the 320i can accelerate from standstill to 100km/h in 8.6 seconds, while the 325i is claimed to dispatch the 0-100km/h sprint in 7.6 seconds.
Standard equipment levels in the 320i are generous, including leather upholstery, multi-function steering wheel, on-board computer, CD player, automatic climate control, fog lamps and 16-inch alloy wheels with low-profile 225/50 tyres.
The 325i is also better equipped than its 323i predecessor, gaining wood trim, a front armrest and a boot-mounted CD stacker.