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Old 09-21-2009, 09:54 AM   #26 (permalink)
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Separate body and frame construction versus uni body with progressively collapsible structure.

Computer design and crash testing have come a long way, but the major component is the separation of the frame and body structure.

I spent 10 years working in auto body repair, and saw literally tens of thousands of wrecks.

One I remember was a 64 Malibu and a 70 Barracuda, in an offset head on collision (about the same as the one in this post). The differences were almost unbelievable. The Malibu (separate frame and body) literally disintegrated, while the Barracuda (uni body with a very strong front cross-member) just folded up in a very controlled manner.

Another thing to consider would be the deterioration of the fasteners in the old Chevy.

That being said the 59 Chevy only had 8 to 10 fasteners holding the whole front end on the car. Two under the radiator support and either two or one at the top and bottom of the fenders in the rear. You could literally remove the whole front end in a few minutes.

Now if you want to go to the extreme, consider the 73 era large Plymouth Fury, used by state troopers in Virginia. I have seen those cars cut a telephone pole in half, and while the damage was bad, it would be nothing compared to a modern vehicle hitting a telephone pole.

The ultimate 60S era tank was the Chrysler Imperial that was uni-body with all exterior panels welded together, except the bumpers and doors, hood and trunk lid. That thing would absolutely crush a modern car.

Chrysler started using uni-body in 1957. The first model I remember using uni-body was the Citroen Traction avant in the 30s.

No trying to be critical of the improvements in collision energy absorption, but I do believe we have gone beyond the point where minor bumper impacts can cost thousands in repairs.

Pops 74 Dodge dart at under 3000 pounds was a tank with those bumpers and the big rubber guards. You could literally bounce that thing off a wall at 5 MPH and break nothing.

In Insurance Institute tested a mid 80s Ford Tempo against a modern plastic bumper car and reached the same conclusion, concerning the high cost of relatively minor low speed impacts.

When I was young and crazy I drove a 63 Valiant Convertible over a slight rise with railroad tracks. The approach side was two feet of elevation while the down slope was at least 6 feet high. I hit it at 55 MPH, and the car flew about 60 feet in the air. When it landed sparks flew out of both sides of the car where the cross-member hit the pavement.

It didn't even knock the front end out of alignment. I had it checked by a friend the next day at the Chrysler dealer where I worked at the time.

regards
gary
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