Natural gas engine maker Westport Innovations has signed a deal with German truck engine manufacturer MAN Nutzfahrzeuge AG to develop a heavy-duty 12-liter truck engine using its Westport-Cycle injection technology. Canada-based Westport and MAN said they would commission an independent market study to examine the commercial feasibility of heavy-duty European trucks equipped with Westport-Cycle natural gas fuel. Westport said it plans to ship a 12-liter MAN heavy-duty truck engine equipped with Westport-Cycle technology this month. MAN expects to complete testing of the engine by September. Westport product director Brad Douville said the Westport-Cycle directly injects natural gas into a heavy-duty truck engine under high pressure. He told Fleet Owner that the system uses a fuel mixture of 94% natural gas and 6% diesel, and the diesel fuel acts as a "liquid sparkplug" to help ignite the natural gas more efficiently. The end result is an engine running almost on pure natural gas that can match a diesel truck engine in torque curve, power efficiency and fuel economy, Douville said. "Natural gas doesn't have the same fuel properties as diesel, so natural gas engines have had to use extra technology such as torque converters in the past to match their diesel-powered brethren," he said. "With this direct injection technology, we don't have to do that -- and that has important implications for trucks spec'd for natural gas." Westport added that it believes its natural gas technology is capable of meeting European Enhanced Environmental Vehicle standards and the testing it is conducting with MAN is designed to confirm that.