[mfain]

This is a tough problem that can open up a whole can of worms - especially for Pro-Touring cars with liability issues on the street and chassis rigidity requirements on the track. NASCAR mandated crush zones a few years back, but the chassis is full of triangulated cage tubes that restore torsional rigidity, especially at the suspension pick-up points- not that practical for a street car. My track car is VERY rigid, with no real crush zones. In a hard frontal crash, the most probable failure point is the little bungee cords (arteries) that your heart hangs on. Modern cars have extensively designed (technically complex, expensive, heavy) crush zones and air bags that absorb a lot of energy. (part of the reason a new Camaro weighs over 4000#) A good 5 or 6 point harness will hold you in place, but a lot of impact forces will be absorbed by your body. A few years ago I put a super late model stock car into a concrete inside wall head-on at over 100 mph. Luckily, I hit just enough on the RF corner that it bent the front clip to the left (2 ft., absorbed a lot of energy) and slapped me rear end first into the wall. The rear clip, with its kick-up built like a crush zone, folded and put the rear end housing 2 ft. up and forward - again absorbing a lot of energy. I still hit hard enough to detach the retina in one eye. Crush zones are a good idea, but would require a lot of expensive engineering/fabrication and would add undesirable weight. One liability issue I would worry about for the chassis shops is replacing factory "crush zones" (like bends in the front frame rails or real crush zones like those on later model cars) with more rigid structures that could result in injuries to a passenger or other involved motorist. People are nuts and will sue for any reason. My $.02 worth.

Pappy