Why do car models continually grow?

[RossABQ]

If there is one dynamic that seems to be constant across all models, makes, manufacturers, it seems to be growth -- in length/width/weight. You almost never see a car reduced.

Ex.: Minivans; the original Caravan/Voyager was a 4-cyl (only) that weighed around 3300# fully dressed up (the basic model was down near 3,000). Even with a feedback carb they were good for around 21/25 EPA mpg. Now you can't find one that is much under 4,000#, all are V6's, mileage is probably 18/28 (due to EFI and OD trans). If a minivan the size of the originals with EFI and OD were built, I have no doubt it would be good for 25/35. All are what used to be "Grand Caravan" length, I don't believe they even make the "short" ones anymore.

Ex.: SUV's; the original Explorers were V6 only, weighed around 3500 even with AWD, were certainly no mileage champs but were still in the 20's. They were also pretty reasonably priced. Now they are just immense! Probably all V8's and in the teens for mileage, near 5000# and $40k+.

Ex.: Honda Civic; they are now as big as an Accord used to be, and the Accord is as big as a Buick. Now they have the Fit down at the low end. Toyota, with the Corolla and Camry, same story.

There are many more examples. Historically in the US model lines, this phenomenon was in full swing throughout the '60's and '70's and progressed to the point of ridiculously sized land yachts that barely fit in a garage.

Why are we still continually moving toward bigger and heavier, instead of smaller cars, given the need for better economy??

 

[safetydan]

The auto industry in the US builds what the public wants, not what their engineers try to design. When the market demands smaller vehicles, the auto makers follow suit, ex. Honda Fit, Chevy Aveo, Mini Cooper.

Crash worthiness is a consideration, but it is not the reason for the increase in bulk of the "smaller" cars. Improvements in design and manufacturing have allowed for smaller vehicles to maintain their crash worthiness without a lot of excess bulk. It is simply what the market wants.

 

[GregLocock]

Well, at the risk of repeating myself.

Say you have a succesful product in the marketplace, and it is time to give it a freshening.

Are you going to downgrade power output? no
make it less crashworthy? no
make it noisier? no
reduce the legroom? no
take out some cupholders? no
take out some features? no

All the pressure is on to increase the above, not reduce it

So are you going to spend millions of dollars so that the external dimesnions and mass of the car can remain unchanged or shrink, while improving it, or do you concentrate on what people actually care about?

To add to Rob's list: the entire British motor industry, except Morgan, Caterham and Westfield.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[firewire67t]

I think a fantastic example of a step in the right direction is the third generation mazda miata introduced in model year 2006. It is an improvement in all the areas that Greg pointed out, most notably size and power output. Meanwhile the engineers painstakingly strived to reduce weight and wound up with a larger more powerful, more comfortable car that weighs less than 50 lbs more than it's predecessor and has much better fuel economy. I understand this is a niche car but the same philosophy can be applied accross the board. bigger and more powerful doesnt have to mean heavier. bigger, heavier and more powerful isn't necessarily an improvement. Maybe when it gets to the point where we have 400 bhp, three axle, chevy aveo's more will recognize this!

 

[patprimmer]

The answer to this is not to keep buying the same model, but to seek out a model that meets your current needs.

For instance if a Camry grows beyond your current needs, buy a Corrola, if a Mazda 6 grows, buy a 3, or whatever name model range applies in your region and to your brand preference.

Regards

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[RossABQ]

Patprimmer, that is exactly what is right to do. In your example, tho, the Corolla has grown to be a nearly Camry-sized vehicle! (the original Camrys) It's a vicious circle.

What absolutely blows my mind is the constant growth of the American light duty trucks. If their gas consumption wasn't bad enough, the current rage is 4-door cabs that are immense, with some of the added cab length coming out of the bed. I'd like to see the EPA slap these with a "car" categorization, it would put an immediate end to that!

 

[patprimmer]

Most SUV and light trucks here are Japanese or European based and they are also growing, but are still not much more than 1/2 the size of the American counterparts in the same load carrying capacity range.

Regards

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