Camera Bug: Car Chassis

Hi, ok, so, when I’m driving a car my frame rate is 60/60 fps, however when ever I look at the bottom of the car my frame rate drops to 5 - 20 fps. Here is an example: (The file was too big so I just uploaded it to Google Drive)

Any idea on what this could be?
Note: I have tried many different car chassis and all of them have the same problem, I do not see this problem occurring in any other game. I need to have to collision of the car on as well.

-Cheers,