If you'd like to vote for the Greatest Car Chase Ever, click here. Each one has the corresponding YouTube video, so you can make up your own mind right there on the spot, and maybe see a couple you've never seen before. Currently Bullitt has a commanding lead, but Ronin and The Blues Brothers are still in the mix.
I, personally, voted for Ronin. Bullitt is too gimmicky, and half the time you don't have any real concept of who's where in the chase.