[Templar]

Depends on the ambient temperature and the inside of your car. Obviously if you have Black Extended inside, your interior will get smoking hot if the sun is beating down on it.

Even the slightest tint on your windows will keep the inside MUCH cooler and your A/C won't have to work as hard to cool the inside. If the inside of your car is extremely hot, it will take a long time to cool down (the leather especially) so it will feel hotter than it actually is. Use a sun-shade on the windshield (since most states don't allow front windshield tint) and have your windows tinted. I guarantee the inside will be way cooler. Window tint does have a few practical uses, not just cosmetics.