Starting in 2005, we migrated away from using a standard camcorder inside the car - which turned out to be a little fragile for racecar work - and started developing a more advanced, durable, and higher-quality race camera setup. We wanted to get solid-state performance like the pro systems - without the $1000 pricetag!
We've now got race footage using the latest setup on Youtube: http://www.youtube.com/profile?user=924RACR
For cameras, we use Sony 1/4" CCD 420 TV line color bullet cams (also called inline or lipstick cams). We now mount one on the front, one on the rear of the roof: an added bonus of this setup is the roof placement gives a camera angle far superior to the inside camcorder setup! That said, we find the 420 line cameras to be a bit limiting in quality, as compared to our recorder, so we expect to eventually pick up a higher-res 520line camera. The cameras are powered direct from the vehicle at 12V DC. Since the cameras are so light, they're easily mounted using velcro and a little homemade metal bracket:
In order to record both camera signals simultaneously, for 2007 we added what's called a quad processor. This is a nifty little piece of electronics capable of taking in up to 4 video signals and merging them in different ways. The default setup is a 2x2 display of all 4 at equal size; we use a PIP mode for the front and rear split, with the rear of course in the small PIP window. When we add a third camera, one of the lower-res 420 line cameras will be placed inside the car for in-car, and this quad processor is capable of doing a dual-PIP mode, with not one but two PIP windows simultaneously. Like the recorder, it's operated by a small remote control. It is also powered, like the cameras, directly from the car at 12V DC.
The video recorder is one of the slickest bits of the whole system; it's a solid-state digital video recorder called the Neuros Recorder 2. It was purchased direct from the manufacturer at http://www.neurosaudio.com/. It has no battery or screen, leading to a very small, light package. It's powered directly from the car, with an adapter (it runs at 5V DC) and is controlled with a remote control - perfect for when you're fully strapped-in on the grid! Below you can see the install; like the cameras and quad processor, it is also small and light enough to be mounted just using velcro.
The final note is the audio setup; we use a small microphone as is commonly found online for around $8. It also requires power (12VDC) from the car; note that this or some such microphone is required when using most bullet cameras as they don't typically come with a microphone (though some do, as noted). If you don't think sound is a priority when filming races, just try keeping your interest on ANY race footage with the sound turned off!! As these microphones are very sensitive, they have to be heavily muffled to work in a racecar without heavy clipping (truncation of the audio signal due to amplifier overload). In our case, they're wrapped up with duct tape and ziptied to the main hoop of the roll cage.