Auto manufacturer rant

[skyl4rk]

If fuel efficiency is an important design goal, then one would expect that automobiles sold today would at least approach an ideal aerodynamic shape to maximize fuel efficiency.

One would hope that production cars would be designed to achieve at least 90% of what is possible using aero designs.

In putting together my boattail, I found an improvement of about 25% by adding some pieces of plastic to the back of my car. I am not an engineer. To me this means that either the automotive engineers are failing miserably, or that automotive managers and stylists are screwing up the product.

Auto manufacturers seem to be able to manipulate automotive styling as they change their designs from year to year.

Why haven't they moved toward aerodynamic styling that improves fuel efficiency? This is not rocket science. An amateur aeromod hacker like me can improve their product by 25% with a boattail. I am sure that there are far more gains to be found in addition to a boattail and in other areas of design (motor, weight, tire construction).

Is manufacturing cost the problem? I hardly think so.

Is aero design ugly and not accepted by the consumer? I don't know this.

Is there some vast conspiracy between oil companies and auto makers? I doubt it.

Do the auto engineers not know how to design cars for fuel efficiency? I am sure that they know how.

Why can an informal group of people on an internet forum make such huge fuel efficiency gains on production cars using simple modifications? It is because automotive manufacturers are failing to design their cars right.

One has to come to the conclusion that fuel efficiency is not a design goal. But there are statements coming from auto manufacturers that fuel efficiency is a goal.

What is going on in the auto industry? Why do I have to buy some cheap pieces of plastic to add to my car to improve mileage? Why don't they figure this out and do it themselves?

Thank you for listening

That is all.

[Weather Spotter]

I bet it has to do with styling + gov regulations. If say they made cars that got 50MPG all the time, the trucks would look SOO bad that they might not be able to make them any more to meet the gov standards.

[Niner]

A big part is the consumer - they just don't really care that much about fuel efficiency. Look at how many people drive SUVs, vans, or trucks to work every day. I had a Dodge Caliber and could get a half sheet (2x8) of plywood in. When I rented a plate compactor to do some concrete prep, the Home Depot guys were shocked I didn't bring a truck to pick it up in.

Ecomodders make up the minority of the car buying world. Some people care enough to pick the better MPG between two similar cars, but just as many would rather have the horsepower. My wife was dead set against me getting a Scion xB because they were "ugly" - no practical concern, pure asthetics. When my mom traded her minivan for a VW Golf, she insisted on the V6 because that's what the van had, and she was afraid of the loss of power. A kammback or boat tail looks smart and sexy to us, but it looks like the fish tails of an old 60's car to other buyers.

That said, engineers could probably put more in without not making it look "ugly". However, that requires that money be spent in that direction, and not necessarily money that will get a good payback. I'm fairly eco-friendly, but I couldn't have told you the reason the Toyota Matrix is more aero frirendly than the Caliber (other than the boxy front end). Auto engineers spend a lot of time just working on repeatability - how do we engineer part A so that the assembler can install it right every time, and that the mechanic can get it off without breaking it and needing to replace it. How much is the tooling going to cost to make this part? Etc. Things that we, as one-off designers, don't have to worry about.

[SoobieOut]

I wonder the same about the automakers. There are two movies which come to mind to explain how crazy and counterintuitive the auto industry has become. One is "Tucker" and the other is "Who killed the electric car?" . Both of these movies illustrate single minded power and profit motives of large auto makers.

When I saw the first Hummer H2 on the road I wondered why would anyone buy such a car/truck? I saw many a soccermom driving alone in the huge SUV while getting 8 MPG. Then I noticed most has a small sign on the door or back advertising a company.

It turns out that our wonderful US tax code allows to deprieciate the full cost of the Hummer in 2 years as a business expense. This is a loophole for Trucks over 6000 lbs. The code was supposed to be used for business trucks but GM exploited the loophole to sell many a gas guzzling Hummer.

I am amazed at the lengths people will go to aviod taxes. In Ciaro, Egypt there are very few windows in buildings. The reason for this is that the goverment taxes by the size and number of windows. So the entire city looks like it was bombed out with open holes in buildings everywhere!

So the solution is to think like a bean counter, since the bean counters make all of the important calls in this country. Give a huge tax break for cars getting over 50 MPG. Then the car companies will build more 50 MPG cars. Simple huh?

The only problem I see with the aero mods from an engineering standpoint is driving over speed bumps in the front, and providing a legal bumper in the rear boattail.

But these can be worked out with the millions spent on R & D on this website ;-)

I had a 1988 Old Calis that got 35 MPG in 1989. GM still can't do that today. So maybe we should have let GM and Chrysler fold. Maybe that is the solution too, stop propping up failing companies and let the market run it's course.

That's my rant for the day.

What's yours?

[bestclimb]

There is already gov standards for passenger cars and a different set of standards for light trucks.

[ConnClark]

Market dictates what sells. Car companies consider a lot in making a car. They are trying to maximize sales and that means juggling several factors.

There are several reasons you don't see boat tails. One is its much more expensive to ship longer cars because you can't fit as many on a truck or a train car. Another is if its too far out looking no one will buy it as it was the case in the 70 Dodge Charger Daytona . Then you have insurance companies getting involved telling the car makers that they will charge more to insure cars with tails that stick out because people are more likely to bump into things with it.

[euromodder]

The strangest thing is that a lot of people actually like the old aero car designs - so why wouldn't they like the new ones ?
It doesn't have to look like or as dull as a Prius.

[Frank Lee]

Originally Posted by ConnClark

Market dictates what sells. Car companies consider a lot in making a car. They are trying to maximize sales and that means juggling several factors.

^Right there is the bulk of it.

You have to realize that we are a fringe group. Even when gas was $4/gal I swear I missed out on the free new Silverado promo as that is what everyone was buying.

That said, I do fault the mfgs for not being proactive when it comes to efficiency matters. They are in a position to do A LOT more when it comes to educating the customer about good driving technique and maintenance procedures i.e. oil changing, selecting the most efficient vehicle, and doing more to make the most efficient vehicles more attractive to more customers.

But what I recall from the '90s and early/mid '00s (when I had TV) was several pickup truck commercials every 7 minutes 24/7 without fail while over a ten year period seeing not a single one advert for the Metro in any print or broadcast.

[Patrick]

Originally Posted by skyl4rk

Is aero design ugly and not accepted by the consumer?

That's 90% of it right there.

[robchalmers]

As said above manufacturers have to guggle a lot of thinks when designing cars. In no particular order:
Styling,
Styling cues from the manufacturer 'face',
Customer acceptence
Crash test requirements
Regional requirements for things like head lights / tail lights
cooling/heating for extreme conditions
cost of repairs
ease of repairs
ease of emergency work (flat tires - wheel covers can be a b*tch on a side of a highway on a wet day)
and of course ........

WAF

well, JPAF joe public acceptence factor..... you'd be surprised how many won't go for a 4ft boat tail on the back or their sub-compact


All of the above though goes against what we've done at Bentley - where we've actually ran a competition for people to pen an aerodynamic concept car in order to help reduce our future fuel consumption
linky