Best way to make a level crossover junction, or crash junction

[KitsuneAmy]

Does anybody know the best way to make a crossover where cars can collide like they do in Bonecrusher or Mission Demo Derby in sandbox? I'm trying to make a track where the center is like a big rectangle where cars can collide.

 

[Anthony]

Does anybody know the best way to make a crossover where cars can collide like they do in Bonecrusher or Mission Demo Derby in sandbox? I'm trying to make a track where the center is like a big rectangle where cars can collide.

View attachment 82659

That's a wired looking track but awesome at the same time.