Yes, you can install power folding mirrors on a 8 foot garage door. However, it may be more costly to do so than to have a new garage door installed. There are many custom auto shops that could add power folding mirrors to your garage door, but costs will vary. Additionally, some car models may have this option already built in. If you aren't sure if your car has power folding mirrors, you can consult with a dealership or online search engine to find out.