The safest way to do car chases is through the power of suggestion. Here's a few things you can do:
-You can create the feeling of going fast by shooting out a side window, other than the windshield, and give the impression of reckless driving by shaking the camera a little.
-For a frontal shot, film the two cars from far away with the zoom at maximum. This will flatten the image and make it look like the cars are a lot closer to each other than they really are. You can also use this when a person on foot is running away from a car. Even major motion pictures resort to this little trick.
-Do a lot of quick cutting from different angles to suggest the feeling of fast-paced action. Believe me, this, more than anything else will set the pace for the scene.
-Use a handheld camera. Some controlled shaking can go a long way in making your scene more exciting. Don't be afraid to make panning shots as a car passes by.
-Accelerate some of the footage. Don't overdo it, as it would look obvious, but making some takes 30% faster can have a good impact.
-Film from both inside and outside the cars. Make some driver point-of-view shots, as well as reaction shots. And how about some rearview mirror shots?
-A good part of suggestion is from sound effects: tires screeching, enginees roaring, etc...
-Don't forget musical sound track. Something fast with a good bass line will help things along.
-You can use the same stretch of road over and over if you change things up a bit. That way you can have an extended chase and only need to find a small stretch of road to commandeer. A lot of major motion pictures use this technique.
-A cheap car mount is to fix a tripod to the front bumper of the car and latch the camera onto the tripod. Make sure it's secure (no duh).
-Another idea is to get in the back of a truck and drive in front of the car with the actors, then shoot through the front windshield. You'll have to dub in any dialogue, and it'll look really shaky, especially if you have to zoom. But check out the car chase in "The Rock" to see how well that can work if you cut it together fast enough.
-In order to fake a fender bender, film from the passenger seat out the front windshield. Frame a wide angle shot of the car in front of you, including a little of the hood of the car at the bottom of the frame for a vantage point. Then, drive toward the car you will "hit." When your car stops, keep zooming, quickly, then shake the camera a bit and add sound in post.
