As Zorg said.
Also, I wholly disagree with bringing Vehicles back, to the point that I would boycott GURPS entirely. It is the number one complaint from GURPS-haters I play with. It was a terrible book. Not because it was badly written, but because it was so granular.
I am sure we have all seen this:
http://s186.photobucket.com/albums/x...PSVehicles.jpg
But, I should caveat that I am very much a KISS GM (as much as GURPS allows), and dump massive amounts of handwavium in my games. I don't see any reason to determine all these sorts of variables. If a player wants to hack that out, fine. But not me...