Coefficient of Drag

It looks like Boo. Other than that those other cars have other means of overcoming air resistance and other very different prime directives. At 200+ mph they squat down and hold the road. I don't need that. I need to plow through the air at lower speeds. Different prime directive. It's OK for now or was that then. Oil at 50$ coming real soon to your neighborhood.

 

I heard that when those high end cars are going at high speed, the drag add an extra several hundred pounds of down pressure. Not really pressure to slow you down but down. those cars also have very expensive v12 engines. as for the corvette. I though the prius was lower. Last time i looked the coefficient of a corvette was .24 *shrug* o well. :mrgreen:

 

the biggest cause of the higher Cd is the large tires used on the cars.

realize that nearly all the air goes up and over the car... but not all does. that is why a spoiler on the rear and air dam on front is necessary.. because there is enough air funneling under and around the car to lift the car off the ground at a high enough speed.

also the Prius creates nearly a straight line from the front bumper to the roofline. no other car does this. the exotic cars you mentioned all have a break in the profile at the base of the windshield.

you will notice the roof of the Prius has the grooves that funnel air to the middle of the roof and down the back. interesting concept and im not sure how it help the coefficient but i have never noticed such a thing on any other car before.

 

<div class='quotetop'>QUOTE(V8Cobrakid\";p=\"42071)</div>

just as help, September 2004 Car & Driver states that the coefficient of drag is .28, Car and Driver Magazine: Chevrolet Corvette

so the prius is pretty low :clap:

 

ther is a ferrari and and a Maclaren that have Cd of .24 and .21 respectively.... the ferrari is the *CHEAP* one at $300,000.

the Maclaren although it is considered an assembly line car is illegal in the US and only about 10-15 are built each year.... estimated cost...$650,000

but if you have the need for a vehicle that goes from 0-100 in 4.8 seconds!! this is your car...

its carbon fiber body is so light that when the brakes are applied over a certain speed, air dams open on the front end of the dam that direct the airflow downwards in an effort to hold the car onto the road...

 

I want the Mclaren F1.. build in 98.. but those cost more around 1 million.. hehe.. and faster than the time you mentioned. It did hold the world record for production car for a while. I'm not sure if it's beat yet. It's illegal because it doesn't have a 15mph impact bumper.. lame

 

for some reason knowing that i have a 15 mph impact bumper just doesnt put me at ease at 200+ mph...

the F-1 went 0-100 in 3.4 secs... but that is out of my price range... and in that case, money doesnt talk as the car was only sold by invitation only...

it did kick nice person at the 24h hours at Le Mans 2 years in a row... only car to do that.

 

hehe.. talking about 0-60..i wonder what the drag of the new Chrysler ME is.. does 2.9 seconds.. people and their horsepower.. hehe

 

Don't forget that the drag coefficient is expressed relative to the frontal area of the object. The actual air resistance calculation uses Cd x frontal area.

A car like a Lamborghini Diablo, even with a higher Cd, will probably have less actual air resistance than a Prius because it's so much less tall.

 

Just knowing there's drivers out there that want to go 200 mph scares me!

I can understand spending a million dollars on a car if you are going to race it and you're betting that you're going to win two million dollars. But in my opinion, anyone who spends even a quarter of a million on a car, just to have it and drive it for fun, ought to be taxed at a much higher rate. Like maybe 99%.

(Same applies to yachts, private jets, mansions, etc.)

 

<div class='quotetop'>QUOTE(V8Cobrakid\";p=\"42088)</div>

15 mph? Meaning if it hits anything at 15+ mph the car gets crushed? Or are we talking the "use to have but no longer" government mandated FIVE mph "damage ONLY to the bumpers and attachments" bumpers. That number is now 2.5 mph. Basically worthless.

 

oh yeah.. maybe it was 5mph.. past my bedtime.. either way, i'm guessing you hit any thing, it's crushed. Then again, with a car that should handle extremely well. I would be doing anything within my power to make sure i don't scratch it.

About going 200+... i would spend that much, if i had it available. A car like the Mclaren can always be sold again. there was one on ebay a while ago.

 

Except you can't control the person that rear ends you when you are stopped because they aren't paying attention. Better get good insurance for your Mclaren ;-)

 

i was watching CNN yesterday at work and there was this guy on a motorcycle who was ticketed for going 145 mph OVER THE POSTED SPEED LIMIT.

his radar gun maxed out at 180 mph... so he had to have the helicopter time the guy...

 

Once in my life I had the opportunity to drive a car like that. It was a Mazarratti (spelling). Some one I know had one and let me drive it on a winding road near where I work. Lots of hills. Great formula one sound from the engine. I headed out on the road and started to run though the gears to 3rd (out of 5). I looked down at the speedometer and it read 85, and I commented to him "oh this is in kph". He replied "no this is the American version that is mph" I have to say I was lugging the engine. That car was glued to the road. I have never experienced anything like it. As I came back at about 75 a 'vette pulled up behind me and started to pass. I dropped the car into second double clutched and as he moved up next to me I left him behind like he was not there. You can still see him to this day on the side of the road curled up in the fetal position. That thing was amazing and I had no business driving like that on city or country streets. I am never likely to get another experience like that and would not do it unless I was on a closed track but I had a brief look into the attraction of such cars. Total power with compleat control. Boggles the mind.

 

It's spelled Maserati.

 

Nice discussion.
Some comparative automobile drag coefficients can be found here:
http://en.wikipedia.org/wiki/Drag_coefficient
I get a kick out of telling people that my Prius has a lower drag coefficient than a Ferrari Testarossa or Lamborghini Countach
However, as previously noted, "drag area" is more relevant.
Anyone know the frontal area of the Prius so we can calculate the "Drag Area"? :huh:

 

<div class='quotetop'>QUOTE(KMO @ Sep 28 2004, 05:19 AM) [snapback]42105[/snapback]</div>

Just for general clarification, drag has, in general, a couple of components,
frictional drag related to wetted area (total surface area exposed to the air), and
pressure drag (our 'drag coefficient' we've been discussing) related to frontal area, and that includes induced drag related to lift and wake drag related to shear stress disrupting the streamline flow paths leading to the lower pressures in the rear of the body compared to the front.
If we could get the prius to approach and exceed mach 1, we would have wave drag to contend with as well.

 

Although it may seem counter-intuitive, sometimes the most aerodynamic shapes don't appear all that streamlined. So a "hamster-shaped" car (I like that one ) is actually efficient, aerodynamically.
DaimlerChrysler has an interesting concept car (a diesel that they say would get 70mpg), and, despite being modeled after a boxfish, it has a Cd of only 0.19:
http://www.greencarcongress.com/2005/06/da...chrysler_1.html