I have owned several GM cars over the years and all of which had the Series II 3800 motor in them. Currently i own a 1999 Pontiac Grand Prix GT with the 3.8L non supercharged. Now on every one of these cars they have an engine beauty cover. Every time i take this cover off. I always figured that it trapped the heat in and robbed power from the motor. Is this true or are my theorys based on nothing? I figured it hasent done any harm in the past so it must not be a bad thing. Right?