When Ronny follows Geneva into the bar during the hockey game and confronts her about the affair, the Chicago Blackhawks are wearing different uniforms on the televisions in the bar then they are in the live game.
When Nick revs up the engine after just starting the car, the temperature gauge is already halfway between C and H. In that brief period of time, the water temperature would not have even started to register.
The temperature gauge in the Charger shows the engine is warm. Electric motors dont generate heat. They also don't produce emissions so there would be no need for a muffler like the ones making the sound in the scene.
When Ronny confronts Geneva about the affair at the Blackhawks game, they miss a goal and the song "Chelsea Dagger" plays which is the goal song for the Blackhawks. In reality, when the Blackhawks score, the goal horn blows followed by song "Chelsea Dagger" by the Fratellis.
When Nick is shown simulating the reving up the car to display their finished product, the water/engine temperature gauge should not even be present since it is supposed to be an electric vehicle made to sound like a gas powered (V8) muscle car by way of a sound system in which these two (Ronny & Nick) have been developing for the automaker, thus the temperature gauge wouldn't be present.