runs just as good in the cold as the heat... Just have to tune for the weather.. richen the high speed needle a bit to compensate for the denser air... Make sure engine is warmed up completely before doing any tuning.. You may have to warm the head before starting with a hairdryer or car heater or the engine may not want to start... Also, remember that the cold weather makes plastic parts brittle.. so go easy on the jumps because the ground is hard like concrete and parts may break easier.. I run all my trucks in the cold weather and never have problems.. other than my hands freezing because of no gloves..