I’ve tried out BMW’s 2.0 litre inline-4 turbodiesel engine used in the BMW 320d and have had good experiences with it, despite the noticable turbo lag. BMW has upped the ante once again with it’s second twin-turbodiesel engine after the 3.0 litre twin turbodiesel used in the 535d and 335d.
The previous 3.0 litre twinturbo was a record in production car turbodiesel application, making 91 horsepower per litre and ridiculously huge amounts of torque. This new 2.0 litre twinturbo inline-4 surpasses that, making roughly 100hp per litre – it’s power figures are 204 horsepower and 400Nm of torque! For comparison’s sake, it’s single-turbo sibling in the 320d I tested makes 163hp at 4,000rpm and 340Nm of torque between 2,000rpm to 2,750rpm.
The 400Nm figure is as much torque as what the new M3’s 4.0 litre V8 makes. All 400 Newton meters kick in at a low 2,000rpm, but that’s not the best part. Half of that, which is 200 Newton meters, is available from just 1,200rpm! That’s only slightly above idle!
The twin turbocharging system is a sequential one, instead of parallel like the 335i‘s N54 Bi-Turbo. In this sequential system, a smaller turbo takes care of the low revs while a bigger one boosts power towards the redline. Despite all that power, fuel consumption is just 4.9 litres of diesel per 100 km.
Opel currently unofficially holds the record of the highest horsepower per displacement for a turbodiesel. It’s OPC division developed 1.9 litre ECOTEC CDTI twin-turbo makes 112hp per litre, for a total of 212hp and 400Nm of torque, which kicks in lower at only 1,400rpm. However, since it’s announcement in early 2004, it has not been used in any production car yet.
One more photo and a torque curve graph after the jump.