The 128i Convertible, which joins the new 1 Series Coupe going on sale in the spring of 2008, will be powered by BMW’s 3.0-liter, 230 horsepower inline six-cylinder engine generating 200 lb-ft of torque. Like its fixed-roof stablemate, the 128i Convertible will feature Valvetronic valvetrain management and aluminum/magnesium cylinder block construction—core elements of BMW’s EfficientDynamics.
The 135i Convertible, on sale later in 2008, features BMW’s twin-turbocharged 3.0-liter inline six-cylinder engine producing 300 horsepower and 300 lb-ft of torque from as low as 1,400 rpm. With its direct piezo gasoline injectors, twin low-mass turbochargers and air-to-air intercooler, optimum performance and economy is achieved with no loss in engine response. For the 135i Convertible, acceleration from 0-62 mph is accomplished in 5.6 seconds and top speed is electronically limited to 155 mph. Both engines feature on-demand engine coolant pumps that improve fuel economy and reduce parasitic losses for increased efficiency.