A system and method for managing the heat produced by operation of an internal combustion system utilizes an electronic controller to control operation the engine that is coupled to a transmission. The transmission can include a high drive ratio and a low drive ratio. Stored in the controller are a plurality of different performance curves. When the transmission is in the low drive ratio, the controller selects a performance curve that comparatively increases the amount of torque and/or power the engine produces. When the transmission is in the high drive ratio, the controller selects a performance curve that comparatively reduces torque and/or power produced by the engine. Because the engine generates less heat when it produces less torque, the engine can accommodate additional emissions control devices and/or techniques that may otherwise adversely affect heat rejection.