Someone raised this issue on another board, and nobody had a really satisfactory answer, so I thought that I’d pose it here, to see if anyone has a better answer.
The 2005 Dodge Charger clocks in at 4150 lbs and a 1960s full size Chrysler sedan weighs about the same (4200 lbs for the 60s model). The 1960s car is much larger than the modern Charger (I can’t find the specs on the new Charger as far as dimensions go, but the 60s Chrysler sedan is 19 ft long and 6 ft wide), so you’d think that the Charger would be a lot lighter (especially since it’s probably filled with plastic and other weight saving materials), but it isn’t.
Even my 81 Honda Prelude, which could practically fit inside a 60s sedan, comes in at 3200 lbs. Why are these newer cars so danged heavy? (On a square foot basis, the new Charger is heavier than the older Chrysler sedan.)
Well, how much of the weight could be attributed to the new systems? The computer, the emissions control, the power steering, air conditioner, fuel injection, and the airbags all come to mind. Do all the new systems have a significant amount of weight?
They’re both made of the same material (steel) and designed to carry the same load (5 people plus luggage). Why would you expect the weight to be significantly different?
Also, I’m sure newer cars provide better protection for the occupants, and that involves a strong steel cage around the passenger compartment.
Power steering dates back to the 1940s, at least. AC first appeared on Packards in 1939, the fuel injectors probably weigh as much as some carb systems. As for the computer, laptops come in around 10 lbs or less, and are vastly more complicated than that used in most cars (certainly my Honda doesn’t have any computers onboard). Don’t forget that older cars used cast iron blocks for engines, while newer cars have aluminum blocks in many cases (and aluminum engines date back to the 1940s as well). Many cars are front wheel drive now, so they no longer have the weight of the drive shaft and rear differential. I don’t know what the weight of airbags are (and that would vary with the number that were in the car), but again, my Honda doesn’t have them, and is dramatically smaller than the 69 Newport I own, yet is only roughly 1000 lbs less in weight than the Newport.
Not a great answer, but my first car a Dodge Dart Sport (essentially a Dodge Charger witha Slant 6 225) had tons of spare room in the engine compartment. The newest vehicles are crammed wall to wall with gear and everywhere you look in a modern car it’s the same. “Stuff” is crammed everywhere. Electronics, power assist stuff, safety stuff, environmental stuff, sound deadening etc.
In older cars things were a lot more minimalistic re onboard gear.
New steel alloys are lighter than ones used just a decade or so ago. Also, newer cars use plastic in place of metal. The bumpers on my Chrysler are chromed steel that’s nearly 1/8th of an inch thick. The steel used for body panels is much thicker on older cars than on newer ones, and many new cars have aluminum bodies (Audi advertised this a great deal a few years ago).
Generally, modern cars are unibodies, which means that the frame is incorporated into the body. This is an easy way to give better protection for the occupants. Cars today are also designed with crumple zones, and according an article I read in Scientific American about 6 years ago, that involves the use of less metal than has been traditionally used.
The other thing is that back in the 1960s, no one really gave a flip about what a car weighed, whereas today car makers literally worry about ounces.
astro, cars are also smaller than they used to be, so car makers don’t have the luxury of having a huge engine compartment, since every inch used for that takes away from passenger space.
Whatever the construction method, you still need a lot of steel around the occupants for safety. I’m sure a 2005 Charger can support several times its own weight placed on its roof, but not the 1960 model.
American consumers still don’t care about weight, as far as I can tell. Maybe buyers of ultra-fuel-efficiency cars and sports cars do, but the Charger is neither.
A Tucker, which basically has an integrated safety cage, is slightly larger than my 69 Newport, weighs in at 3600 lbs.
American consumers aren’t designing cars.
Another thing I forgot to mention is that the amount of horsepower engines develop is increasing, so designers can get away with using smaller engines. The 383 V-8 in my Newport is rated at 255 HP, which is the same amount of HP that the four banger in the 90 Pontiac Grand Am I used to own, put out.
Of course not, engineers design the cars for American consumers. They know the consumers don’t care much about the benefits brought on by reduced weight. At least not the target market of a Charger.
Bodies in gray are definitely lighter than in yesteryear. And they’re getting lighter and lighter all the time. Metal guages are significantly thinner. Advance high strength steels and boron steels are making metal stronger, thinner, and lighter all of the time. Certain closure materials (“skins”) have no significant safety or structural purposes and can be made from magnesium, aluminum, or even thinner steel. The elimination of frames reduces weight to a considerable degree. A complete body in gray is very lightweight and can be pushed around on a concrete floor (no wheels or dollies or anything) by a single person.
I don’t do powertrain or trim or paint, but it’s probably one of them adding all of the weight. I can tell you conclusively that it’s not in the bodies! Granted I’m talking about “normal” unit-body cars and small SUV’s here – nothing body-on-frame.
Below a certain weight, cars are just begging to be moved by drunken college students.
My 88 Ford Festiva moved quite a bit around the parking areas of U. Mass Lowell. 1600 pounds or so.
I’m sure that it didn’t have anything to do with why they don’t build “little, light” cars though.
Strangely enough, my 98 VW Golf weighed in at about 3600 pounds, and wasn’t all that much bigger than the Festiva. I was never really able to figure out why it should be double the weight.
To the best of my recollection, the best engine you could get in a 1990 Pontiac Grand am was the High Output “Quad 4” engine that GM was producing at the time. (It was called a QUAD 4 because it had Dual Overhead Cams and 4 valves per cylinder).
Good question. Ask Toyota, they’ve got at least one, and I’d be surprised if their engineers hadn’t run the design through crash test simulators.
Engineers also have to worry about CAFE standards, and the new Charger is still smaller than either a 60s Newport or a Tucker (by several feet).
Philster, seems high to me as well, but I read that some place, danged if I can remember where (may have been in the Haynes manual I had for the car, in which case it’s most certainly wrong), so taking crazyjoe’s number as being correct, then you have an engine with half the cylinders having almost the same HP as an engine with double the cylinders. A Tucker (with a flat six 335 cu in. engine ) was only rated at 103 HP (and was a high performance helicopter engine), so we’re definately squeezing more ponies out of smaller engines.
Smaller engines have more ponies per cubic inch, better power bands and some sacrifice in torque (inherent in smaller, oversquare engines in which the piston stroke isn’t even equal to the cylinder diamter), meaning revs are used to build power.
But power now is transmitted through four and five-speed auto-transmissions, often electronically controlled to provide combos of accel, cruising and economy.
A modern car doesn’t need the power to weight ratio some old sleds did, as many older cars were making due with simple two-speed trannies, and sluggish-to-respond carb setups.
Weight? Well, there is a ton of technology adding hundreds of pounds, and tons of convenience kicking in the weight as well.
Lots of good answers. It’s a combination of more systems, more complex suspensions, more soundproofing, safety (reinforced pillars, side impact protection, etc), more complex engines and ancilliary equipment, etc.
But here’s another one - chassis stiffness. Cars today are just way, way stiffer than older cars. Less flex means a more controllable, predictable platform for hanging suspension pieces on. It also means closer tolerances for body panels, fewer squeaks and rattles, no cowl shake, suspension that can be tuned more precisely, etc. A large part of the stiffness of new cars comes from computer-aided design, but lots of it is simply additional bracing. And that adds weight.
Another thing that adds weight is platform sharing. Auto platforms (the chassis, suspension, electrical system/bus, etc) is so expensive to develop that car companies share the platform among many different vehicles. So if your sedan shares a platform with a light truck, chances are the platform for the sedan is heavier than it needs to be.