The B6.7N is certified to California ARB optional Low NO_x standard of 0.1 g/bhp-hr—a 50% reduction from current EPA levels. Available with ratings from 200 – 240 hp and 560 lb-ft (759 N·m) peak torque, the B6.7N is suited for school bus, shuttle, and medium-duty truck applications.

Based on the ISL G and ISB6.7 G natural gas engines, the 2018 L9N and B6.7N build on the experience gained from more than 80,000 Cummins Westport engines currently in service and provide a present-day solution to urban air quality issues. In addition to ultra low emissions, the L9N and B6.7N feature a new engine control module with improved durability, on-board diagnostic (OBD) capability, an enhanced maintenance-free three-way catalyst, and a closed crankcase ventilation system.

All CWI engines offer customers the choice of using compressed natural gas (CNG), liquefied natural gas (LNG), or renewable natural gas (RNG) as a fuel. RNG is pipeline-quality natural gas produced from the decomposition of organic waste, which can come from a variety of sources such as dairy farms, landfills, and urban waste treatment plants. Combining Cummins Westport’s ultra low emission engines with RNG fuel provides additional and significant GHG reductions.

For 2018, the L9N and B6.7N will be available as a first-fit option from leading bus and truck manufacturers. Cummins Westport will also introduce the ISX12N natural gas engine as a first-fit option, which like the L9N, will meet the Optional Low NO_x emissions level of 0.02 g/bhp-hr. With 400 hp / 1,450 lb-ft (1,966 N·m) torque, the ISX12N is well suited for heavy-duty regional-haul truck/tractor, vocational, and refuse applications.

Production of all three engines will begin in the first quarter of 2018.

CWI acknowledges engine development funding support from the Gas Technology Institute, South Coast Air Quality Management District, SoCalGas, and the California Energy Commission.