25 May 2013

Ever Ask Why They'd Never



Oh, it's even a Communist style five point plan!
1. Increase noise 

Yeah, that will cause people to slow down.  Pay attention to how fast the loudest cars are going.  Noise does not get people to slow down.  The best way to figure that out is to notice that speeding tickets have been issued for decades, issued to cars that lacked all of the fancy sound deadening and vibration reduction of modern cars because such refinements had yet to be invented.

2. Reduce standard equipment

Reducing the weight of the car will have a positive effect on its mileage, but what adds the most weight to a modern car is not the luxury appointments but the mandatory safety equipment.  On average it adds 600 pounds to a car, and you're complaining about the drag of an alternator?

An alternator sucks up about 1hp per 25 amps at full load.  A whopping 4 horsepower with the typical car today.

Lugging the equivalent of three full sized greenies (or two Americans) around everywhere you go has a much larger effect on your mileage.

Air-conditioning is also blamed for killing mileage.  At full tilt they consume about 10hp (compared to about 25hp in 1979!).  You'll find lots of internet answers claiming they consume 20% of engine power.  Who makes a 50hp car?  But is is better to run the AC or leave the windows down?

That depends.  How much extra drag is imposed by rolling down the windows?  That drag increases logarithmically as speed increases, so it will also depend on speed.  The base aerodynamics of the car matter a great deal as well.  No matter what though, there's a point where the increased drag from the air will cost more than the cost of running the compressor.

3. Radical aerodynamics

They act like this isn't already happening.  That cars still can be designed to look appealing after leaving the wind tunnel is a testament to the talents of the aerodynamic engineers who actually know and understand this topic compared to a greenie with a journalism degree.

How do I know Mr Greenie doesn't understand aero?  Point 1 gives it away.  Wind noise is a sign that air is not flowing smoothly.  That causes drag and drag consumes energy.

4. Tandem seating

Here he's right.  Decreasing the frontal area is a proven way to decrease drag.  To a point.  Area ruling is something he might wanna look up, but for a car sized object there's not a lot you can do.  The real problem with tandem seating for a car is utility.  (By the way, your typical car already has seats in tandem, the back seats are tandem to the front seats... DUR).  A two seat car with tandem seats is aerodynamic and forgets that we use our cars to get stuff from the store.  It also overlooks that many people need more than two seats.  It's the same reason the Smart 4-2 and Corvette aren't in more driveways, where's the kid gonna sit?

Form follows function and the form of the automobile did not pop out of a vacuum.

5. Delete gas-guzzling engines from the range


Define gas-guzzling.  The "gas guzzling" V-8 in a new Corvette is a 450 horsepower 6.2L engine that gets 30 miles per gallon (epa calculated).  It replaces a similarly powered engine that gets 26 miles per gallon.  A 450 horsepower engine in 1965 is a NINE miles per gallon engine that also weighs twice as much!   Additionally, the Corvette engine has been getting more displacement, more power and better mileage since 1984.  Derivatives of these engines can be found in full sized pick-ups and the mileage improvements are much more felt.

A 1975 Pinto with an 83 horsepower 2.3L 4 cylinder and a manual transmission only got 34 miles per gallon.  The Vette engine is 542% more powerful and "only" gets 88% of the mileage.

A 155 hp 2.0L 4 cylinder engine in a manual transmission Mazda 3 is eking out 39 mpg with the same technology as the new Corvette.

He mentions that car makers must sell cars.  It should be pointed out, firmly, that every car made that embraces all five of his points is not being sold today.  No car company that embraced all but #4 are still in business.


3 comments:

  1. Dude - this epically beautiful.

    I wasn't aware the 450HP Vette got 30 MPG. I drive an SUV because I tow a boat now and then, and my V6 Explorer gets 22 MPG highway. Nowhere near that Vette's efficiency.

    Engine designers haven't been asleep the last 40 years.

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  2. My 436hp Vette is supposed to get 19 City, 26 Highway and I've seen 25 routinely in mixed driving and 27-29 is not unheard of on long interstate trips.

    It really puts things in perspective about power and mileage. My old '86 Civic hatch's engine was a 1.3L making a soul crushing 60hp@5,500 and 73 ft-lb@3,500. It was rated at 31/39. I got 40 pretty regular. I'm fascinated that my friend's 2013 Mazda matches those economy numbers and gets almost three times the power.

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  3. Regarding the linked article:
    Point 1. The author's contention seems to be that more noise, wind roar, and vibration make a driver go slower. Consider a motorcycle - loud, lots of wind roar and vibration. Motorcyclists the world over are renowned for their low speeds and cautious driving habits; an obvious correlation.

    I have a suggestion that I think more directly employs the idea of irritating the driver into the desired behavior. Install an air horn in the driver's headrest, and wire it to sound continually whenever the vehicle is travelling over 60 mph. This would cause the driver to more strictly monitor his speed, without sacrificing ride quality at more reasonable speeds.

    Point 2: I feel we should take the idea of economy through austerity and run with it. Do you realize how much seat cushions weigh? There are pounds and pounds of unnecessary foam in modern vehicles. Do you know that NASA saves 600 lbs of weight on the shuttle's external tanks by not painting them? Why shouldn't we follow their bold example! Removing the environmental controls and entertainment system should only be our first step. I suggest we forge boldly ahead and save many tens of pounds by removing the modern extravagance of dash instrumentation. An experienced driver should be able to judge his speed by road and wind noise, and should know how much fuel remains in his tank by tracking his mileage.

    Point 3: Radical Aerodynamics. I'm sure major auto manufacturers aren't much concerned over the aerodynamics and fuel economy of their decadent new cars. They could certainly do more to improve the drag coefficients at the expense of their "giant headlight" styling. For example, the 2012 Mazda3 has a 0.26 Cd, and the Toyota Prius has a 0.25, compared to the 1979 Ford Mustang coupe's 0.46, or the legendary Lamborghini Countach's 0.42! Why are we not working on this, people!

    Point 4: Reducing the number of seats is an excellent way to remove weight, increase performance, and improve aerodynamics all at once. Ideally, each of us would drive a single-seat vehicle, probably in a prone position for aerodynamic reasons. Let us do away with the carpool lane! To hell with you if your luggage doesn't fit in your pockets! All will bow to the god of efficiency, and eventually we will reach the ideal state. Zero seats.

    Point 5: Here the author points out that consumers want access to V6 and V8 engines, and concludes from this evidence that auto manufacturers won't be making high-efficiency vehicles anytime soon. Clearly the average consumer in today's auto market is unconcerned with fuel economy. And because of this lack of consumer interest, technological advancement by automakers is a dead end.

    It's a tragic conclusion, but I see no way to refute it. The modern consumer desires nothing more than a return to solid steel engine blocks and styling reminiscent of Rolls-Royce.

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