First off- I congratulate you on the best approach to this game jam- making a game about a jumping car. Now, cynics could say "kkcn only says that, because he ALSO made a game about a jumping car", but that's completely backwards- I made a game about a jumping car, because that's was the best way to approach this jam, as you'd surely agree!
Jokes aside- great game. I didn't finish it- the last wave proved too much for me at 23:00, but I'll probably try to finish it tomorrow. Graphics and sound work together to really sell the JUICE of the game. Crushing the cop cars feels great, so does lining a couple of them to damage them all in a single shot. It's simple to learn, fast, stylish and hella juicy! Great work!