Cummins Westport Inc. has begun development on the ISB6.7 G natural gas engine that the company said is designed to meet the increasing demand for on-highway vehicles powered by lower cost, cleaner alternative fuels. It is expected to be in production by 2015.
The 6.7L G engine is based on the Cummins ISB6.7 diesel engine for school buses and other medium-duty vocational vehicles. It will use Cummins Westport's spark-ignited, stoichiometric cooled exhaust gas recirculation (SEGR) technology.
The company added that exhaust aftertreatment to meet EPA and California Air Resources Board regulations will be provided by a simple, maintenance-free, three-way catalyst.
While the ISB6.7 G will run on CNG, Cummins Westport said natural gas may also be stored on the vehicle in an LNG state.
"The addition of the ISB6.7 G will round out our family of high performance natural gas engines," said Jim Arthurs, president of Cummins Westport. "It joins the 8.9-liter ISL G, with over 16,000 engines in service, and the 11.9-litre ISX12 G, which will start production in 2013, to give our customers a broad range of natural gas engines for on-highway applications."
Cummins introduced its ISB6.7L diesel in 2007. It replaced the 5.9 liter engine to meet stricter emissions requirements.