Both engines are compact four-cylinder units that use turbochargers to make up for their lack of displacement. The petrol unit delivers an 8% fuel consumption saving compared to a naturally aspirated engine with the same output of 120hp to 140hp.
The 1.6 liter CNG unit is more powerful than its smaller petrol brother, churning out an estimated 150hp and 210 Nm of torque. It also cuts CO2 emissions by around 25% when compared to a similarly powerful petrol engine. The CNG unit will likely be used first in the 2009 Opel Zafira minivan although there is no word yet on what other products, including U.S. models, will be using the two engines.
Combining small engines with turbo chargers to reduce emissions but maintain performance has been a simple yet effective strategy for manufacturers, especially in light of tougher emissions laws. Turbocharger manufacturer BorgWarner, in fact, has been so convinced of increased turbocharger demand that the company is ramping up production and even building new plants in order to quell demand in the future.