BMW has added an important new four-cylinder derivative to the successful Z4 line-up and first deliveries will arrive this month in the UK. The new 16-valve engine is the same, 1,995cc unit featured in the BMW 1 Series and the latest BMW 320I Saloon and produces an impressive 150bhp at 6,200rpm and 200Nm or torque at 3,600rpm.

The Z4 introduces a new entry-level point for BMW roadster ownership at £22,755 on-the-road. An SE version adds additional specification to an equivalent level as the six-cylinder Z4 2.2I SE, including the Z4's super-fast automatic folding soft-top, front fog lights, heated door mirrors and an on-board computer. The Z4 2.0I SE is priced at £23,465 on-the-road. The four-cylinder engine is made exclusively at BMW's Hams Hall engine facility in Warwickshire and is EU4 compliant. It offers significant power and torque increases over BMW's previous four-cylinder petrol unit.

These have been achieved by improving the intake and exhaust systems while a new electronic control unit provides a more instant throttle response to a level only previously achieved on engines with individual throttle butterflies such as M3 and M5. Meanwhile VANOS (variable valve timing) and Valvetronic valve lift ensure a strong engine response through the gears. Zero to 62mph now takes just 8.2 seconds, virtually a second faster than the acclaimed new BMW 320i.