A full range of 2013-model year truck engines is being shown off by Cummins at the World of Concrete show in Las Vegas this week – including the new 12-liter natural gas-fired Cummins Westport ISX12 model, due to start limited production this April.

Cummins said its 2013 on-highway diesel engines designed for vocational applications, including the 12-liter ISX12 and 9-liter ISL9, should provide up to 2% better fuel economy compared with its 2012 model year engines – with both certified to meet 2013 U.S. Environmental Protection Agency (EPA) greenhouse gas (GHG) and fuel efficiency rules that take effect in 2014.

The ISX12, with ratings from 310 hp to 425 hp, offers over 800 lb-ft of clutch engagement torque in addition to special “SmartTorque” ratings that deliver an additional 200 lb-ft of torque in the top two gears, noted Jeff Jones, VP of North American engine business and market communications for Cummins – making it ideal for concrete mixers, dump trucks and refuse haulers, he pointed out. The ISL9, by comparison, offers ratings from 260 hp to 380 hp, he said.

Jones added that the company’s Cummins Westport natural gas engines – the ISL G and ISX12 G – use the same base engine and key components as their diesel counterparts, but feature Cummins Westport's proprietary spark-ignited combustion technology with Stoichiometric cooled exhaust gas recirculation (SEGR) alongside a three-way catalyst.

He noted that the ISL G – which is certified to the EPA’s 2013 GHG rules – is available with ratings from 250 hp to 320 hp. The ISX12 G offers ratings from 320 hp to 400 hp plus up to 1450 lb-ft torque, with optional features such as engine braking as well as compatibility with automatic and manual transmissions, and will be EPA 2013 certified when limited production begins in April.

Cummins pointed out that the ISX12 G and the ISL G can operate on either compressed natural gas (CNG), liquefied natural gas (LNG) or biomethane.