Every Alternative: Cummins Westport ISL G

The 8.9-liter ISL G has met EPA 2010 emissions standards since 2007 using Stoichiometric cooled-Exhaust Gas Recirculation (SEGR) spark-ignited combustion to create a high-performance natural gas engine.  Torque at idle and fuel economy are improved versus lean-burn engines by 30% and 5%, respectively.

Cooled EGR, in combination with stoichiometric combustion (the theoretical or ideal combustion process in which fuel and oxygen are completely consumed), creates an oxygen-free exhaust, which allows for the use of Three-Way Catalyst (TWC) aftertreatment.  TWCs are effective, simple, passive devices that are packaged as a muffler and are maintenance-free.  The ISL G does not require active aftertreatment such as DPFs or SCR.

The Natural Alternative.

The ISL G is rugged and reliable because it shares many components and parts with Cummins L Series diesels and is built on the same assembly line as Cummins diesels.  A wastegated turbocharger with electronic control for precise air handling and full drive-by-wire throttle control provide impressive diesel-like performance.

A new ECM provides full monitoring and control of engine sensors, fuel system and ignition system.  The ECM provides full interface capability to Cummins INSITE™ and diagnostic service tools.  It also provides Original Equipment Manufacturers (OEMs) and end users with the ability to tailor performance of the engine to fit the vehicle mission.