BMW 3 series

By Dan Gilbert

14th August 2006

BMW has announced that the 3 series range of saloon and touring cars will get three new six-cylinder engines in September this year, including its most powerful diesel ever.

The engines will go into the key models in the range, starting with the 3-litre petrol turbo, to be badged the 335i, which will push out 305bhp, 400Nm of torque and shift the saloon to 62 mph in 5.6 seconds, while returning nearly 30mpg.

The single-turbo diesel, the 325d, produces 197bhp, the same 400Nm of torque, a 7.4 second time to 62mph and an incredible 44mpg overall.

However, the centrepiece of the launch is the innovative twin-turbo diesel. This awesome oil-burner churns out 286bhp, an astonishing 580Nm of torque, around 37mpg and gets to 62mph in a fraction over 6 seconds - true sportscar performance from a six-pot diesel! The key is a different take on twin-turbos - instead of each one supplying 3 cylinders, both turbos apply to the whole engine, but at different times.

The smaller turbo kicks in at low revs, so that 95% of full torque comes online at just 1500 revs, while the bigger turbo takes over as the revs head up to the power peak of 4400rpm, to keep the power coming smoothly.