International Truck and Engine Corp. on Thursday, March 22, at the Mid-America Trucking Show in Louisville, Ky., revealed the power and torque ratings for its MaxxForce 11 and MaxxForce 13 Class 8 engines, and released other news about its new ProStar Class 8 tractor. Those engines will be available by year’s end, said Jacob Thomas, vice president of the Big Bore Diesel Engines Business Unit.
Six MaxxForce big-bore models offer ratings of 330 to 475 horsepower and 1,250 to 1,700 lb.-ft. torque. The efﬁciency and power characteristics of the MaxxForce 11 and MaxxForce 13 are made possible in part by a high-pressure common-rail fuel system, twin-series turbochargers with interstage cooler, and Eco-Therm, International’s heat-management system, Thomas said. Eco-Therm features an innovative, multiple coolant circuit design managed by an electronically controlled coolant control valve.
The advanced fuel-and air-management systems of the MaxxForce engines provide instant response to reach peak torque at 1,000 rpm. This means earlier acceleration upshifts and fewer grade-climb downshifts, Thomas said. This keeps MaxxForce big-bore engines operating more often in the lower speed range, where fuel economy is best.
International also announced: