by The_Toecutter » Thu 22 May 2008, 23:14:02
$this->bbcode_second_pass_quote('kokoda', 'T')he car is only ugly because of the standard of workmanship.
It makes you wonder just what a professional designer could do starting from scratch.
If you could optimise the shape even more, reduce the weight and marry it with a super fuel efficient engine, perhaps even electric, then imagine what sort of economy you could get.
An example of a few midsize and full size cars through history:
1921 Rumpler, .27 drag coefficient
1935 Tatra T77a, .21 drag coefficient
1954 Alfa Romeo BAT7, .19 drag coefficient
1953 Hotchkiss Gegoire, .25 drag coefficient
1984 Chevrolet Citation IV, .18 drag coefficient
1985 Ford Probe V, .137 drag coefficient
1998 Dodge Intrepid ESX2, .19 drag coefficient
2000 Ford Prodigy, .20 drag coefficient
2000 GM Precept, .16 drag coefficient
For comparison, the new Toyota Prius is the most aerodynamic car any mainstream automaker will sell in the US. It has a 0.26 Cd. The 1921 Rumpler was getting close to that...
I can give you many, many more from this, and fuel economy/performance figures if you're interested(I've compiled a list of over 80 highly efficient cars from the distant past to presentlisting engine type, Cd, weight, fuel economy, performance specs, ect. I've showed a partial list to yesplease months ago). The automakers were building 60+ mpg prototypes since the 1970s that worked, looked normal for the cars of their era, and typically had no performance penalty. The 1983 Volvo LCP 2000 did 0-60 mph in 11 seconds, got 86 mpg highway on diesel, topped over 110 mph, could seat 4 adults, was a small station wagon, in volume production would have incurred no cost penalty to the consumer according to Volvo themselves...
We could have been doing this
without any sacrifice on part of the consumer.
Cutting the Cd of cars from about 0.32-.34 average in the U.S. today down to 0.16-0.18 would allow a 180 horsepower 3L V6 midsize car weighing 3,400 lbs to go from vabout 27 mpg combined to 45 mpg, just by cutting the drag alone. This doesn't include reductions in frontal area(from reduced size), doesn't include reduced weight, doesn't include reduced horsepoiwer or reduced engine displacement, doesn't include newly available engine technologies such as hybrid drives or clean diesels...
Through aerodynamics alone, we could have 40+ mpg highway 7L V8 musclecars. It takes about $400 million for the major automakers to design a car from scratch and build all of the production facilities and get a car crash/emissions/ect. tested and mass produced. $5 million more in wind tunnel testing along with designing the cars for efficiency(instead of telling engineers not to go below a certain drag coefficient) would go a LONG way. Halving the drag coefficient would yield about a 40% gain overall, possibly more with the right design.
Would the aerospace industry not have a monopoly on carbon fibre, the aerospace grade stuff needed for cars would drop to $10/lb, giving it no cost penalty over steel. This would reduce the weight of todays cars by 600-800 lbs, giving an increase in fuel economy of about 25% in the city and 5-10% on the highway.
BUT, load reduction(lowering aero drag, rolling resistance, ect.) also means less wear and tear on parts, and less money flowing from Joe Sixpack to the auto monopolies. So, in the 1970s, when Joe Sixpack wanted fuel efficiency, Detroit decided to punish J6P with anemic, cramped econoboxes. Take a normal 27 mpg midsize car with a 3L Otto cycle V6 that does 0-60 mph in 9 seconds, remove the V6, replace with a 25 horsepower 3 cylinder Otto cycle engine, and fuel economy will only increase to about 35 mpg or so, while 0-60 time will now be measurable in minutes and even with no governor, top speed about 75 mph, 70-ish if you use air conditioning. The automakers could have kept the V8s in the 1970s, addressed weight and drag, and made some very good cars. But, that would have meant less money per vehicle sold, and especdially with the oil industry and auto industry investing in each other, even if profits in the auto sector increased from vitalizing sales, the profits lost in the oil sector would be far greater., Therefore, they won't do it. Oilies have too much control.
I could give you the equations to model a car's fuel economy if you are interested. They would be accurate within about 5%. You could use these to design your own concepts. Basjoos' civic is probably around a 0.16 Cd. An aeronautical engineer named Phil Knox also has an aeromodded Honda CRX that gets 90 mpg highway at 70 mph.
Once I find a garage down here in Texas where I can mod my Ford Contour, it will be getting ~45 mpg highway. Stock, it gets about 27 mpg highway according to the EPA and I measured 28 mpg at 70 mph driving to Texas. It has a 2.5L 170 horsepower V6 doing 0-60 mph in 7.7 secs, stock. Then I will add a supercharger to it, get ~300 horsepower, and still get 40+ mpg on the highway with this mod, and an
insane top speed if I ever decide to adjust the gearing too.
The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson