If you're going to have the entire 1.5TB in your car then you're going to have a problem.
The largest laptop drive is 80GB at the moment so you're going to need around 20 of them. If you're willing to risk using a desktop drive then it's 250GB each and you're going to need about 7.
It's preferable to use a laptop drive as they're designed to handle bigger shocks and use less power.
If you're not intending to have it running when you're moving then it's not important if you use a desktop drive.

Interesting project however

- Trevor

[edit]Forgot about 250GB drives[/edit]