The Orange County Transportation Authority (OCTA) has ordered 531 Cummins Westport (CWI) transit bus engines to be installed as a combination of new installations and repowers (installation of a new power plant in an existing vehicle chassis).
The new installations will begin in March 2007 and the repowers will begin in May 2007. The 531 engine order is made up of both the 2007 ISL G and the C Gas Plus engine models. This marks the second major order for the new 2007 ISL G. (Earlier post.)
The 8.9-liter ISL G will surpass EPA and CARB 2007 phase-in levels and meet 2010 emission standards of 0.2 g/bhp-hr NOx and 0.01 g/bhp-hr PM at launch in 2007.
Based on the Cummins ISL, the ISL G leverages Cummins proven Exhaust Gas Recirculation (EGR) and stoichiometric combustion allowing for the use of a three-way catalyst, which is maintenance free and has been in common use in passenger cars since the 1970s.
In addition to delivering ultra low emissions, the ISL G, with ratings from 250 to 320-horsepower, will deliver increased thermal efficiency and more than 30% higher low-speed torque compared with current Plus engine models.
Orange County Transportation Authority (OCTA) operates a fleet of more than 500 buses, and also has authority over commuter-rail services, freeways, street and road improvement projects, motorist aid services and regulating taxi operations.