I was having a little too much fun today with a 4 star police chase.
I fount the best way to smash through blockades and oncoming cops so that your car lasts longer is to hit the E brake right before the impact so that you slide sideways into the other car... I used the Bullet GT in TBoGT and the Turismo in the regular... The Bullet lasted about 6 minutes. The Turismo lasted about 13 (and that was with me smashing into stuff constantly)
Stick with a Mid or Rear engine car for those collisons you can't avoid and you'll be golden.
Also if you time hitting the blockade just right, the impact will actually put your car in the direction yo were travelling with little loss to your original speed (given you were at top speed.)
It may be obvious to some, but I had no idea just how effective that maneuver is. Enjoy, and let me now how it goes for you guys. (and gals)