Joining the 1-series coupe in showrooms in the spring of next year will be the 128i Convertible, which will be powered by BMW’s 230hp 3.0L straight-six. The engine features Valvetronic valvetrain management and aluminum and magnesium construction for its cylinder block. Arriving later in 2008 will be a 135i Convertible, complete with the potent twin-turbo 3.0L engine and all 300hp and 300lb-ft of torque. 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 – peak torque arrives as low as 1,400rpm.
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 cars feature on-demand engine coolant pumps that improve fuel economy and engine efficiency.