The additional output will allow drivers to hold the truck in gear for longer, which can be advantageous in some applications.

IVECO Australia has announced an additional power rating for International ProStar models, providing buyers with a new 600hp/2,050 lb/ft (447kW/2,779 Nm) option, along with the existing 550hp/1,850 lb/ft (410 kW/2,508 Nm variant) rating.

The additional power has been achieved via calibration changes to the ProStar‘s 15-litre Cummins X15 engine, in a successful joint project between International‘s Australian engineers and the team at Cummins South Pacific.

International engineering manager, Adrian Wright, says the additional output rating was a logical step in offering prospective customers a second power option if the application required it.

“For the initial development program, we focused on the 550 horsepower/1,850 lb/ft rating, as this was the most commonly specified in the B-double conventional market segment,” Wright says. “But it was always our plan to look at the 600 horsepower rating at a later stage. With increased ProStar sales activity and a growing enquiry rate on both 550 and 600 horsepower ratings, the timing has worked well.”

In bringing the 600hp option to market, Wright says that there was close collaboration between International‘s local engineering team and Cummins South Pacific.

“We re-evaluated a full production spec truck and tested it extensively both on the road and on the dyno,” he says. “The truck performed exceptionally well and easily met all of Cummins‘ stringent requirements for Australian heavy haul applications.

“The 550 horsepower engine is a strong performer but the additional torque of the 600 horsepower engine will allow the truck to hold a higher gear for longer which can be advantageous for certain applications and can even help save fuel in some circumstances.”

Both engine ratings can be specified across the entire ProStar range, encompassing tipper, day cab, extended cab, and sleeper cab models, with either the Eaton 18-speed manual transmission or Eaton‘s clever UltraShift PLUS 18-speed automated manual.

Cummins X15.jpg:  A 600 hp/2,050 lb/ft ((447kW/2,779 Nm) power option is now available for all Cummins X15-Powered ProStar models.

Intertruck managing director Comer Board says New Zealand has a different ambient temperature from Australia, which meant the higher capacity engine was approved to run here from its release in March 2017.

He says at the other end of the scale Intertruck have released a lower rating X15 – 485hp with 1850lb/ft – in the ProStar LX (LX denotes ‘Lightweight‘).

“New Zealand assembly allows specific high-tech components installed, including a new second steer ECAS Air suspension, saving a further 70kg and delivering weights similar to our WorkStar model but with a 15L engine.”