Forums > Off the beaten path

Why cars don't get 50mpg

Posts (17)

  • quazz4life

    quazz4life

    #30464968 - 10 years ago

    via Newsweek.com

    An interesting article on why cars aren't already getting 50 mpg. and while it's an interesting read, another thought hit me towards the end.
    If plug-in electric cars do become the norm, who's going to pay for all of the electricity used to charge them? Also, who is going to pay to have all of those millions of parking stalls retrofitted to have plugs readily available?
    I live in an apartment complex, and I'm having trouble seeing how I can plug in my car. The closest outlet I have would require three 50 foot extension cords to get to my car. and that's assuming that my voltage/ampage is even the same.
    So how much would that car really end up costing you, if you are like me and live in a place that does not have a garage?
    I can't see landlords coughing up that kind of money themselves, so the cost would probably come with upping my rent. and I'm sure that outfitting the many hundreds of stalls with electric outlets isn't going to be cheap.
    don't get me wrong, I'm all for this idea that would eventually break us from our oil dependence, I'm just worried about the logistics that seem to have yet to be thought of or addressed.
    thoughts?

  • breakbread

    breakbread

    #30464969 - 10 years ago

    A mid to late 80s Honda CRX got 40mpg easy. The problem is, to an extent. Have you looked at how fucking big cars are these days? My 1996 Integra ways 2600lb. I get about 30mpg on the hwy, which was about the norm for a small car back then. However, you take a modern 1.8l Honda engine that already gets 35mpg or so and drop it in my car, say hello to 40mpg+.

    An e30 325 weights in at 2,780lbs
    And e92 325 is knocking on 3400lbs' door.

    Now, I'm not a physics major or anything, so maybe someone can chime in on this. But I think, once you get to a certain speed, the weight of an object is no longer a penalty when increasing the speed. I don't know how much this plays into things. I do know, thought, that we've more or less been breaking even the past 10 or 20 years. Engines have gotten vastly more efficient, but cars are heavier which cuts into to efficiency gains. We now have direct injection and cylinder deactivation, which are great, but the weight just keeps going up.

    On another subject, the Prius is moving things in the right direction, but it's far from the savior of Global Warming. The Greenest car of the year was awarded to a diesel Volvo. That's right, a car that runs on dead dinosaurs beat out the feel-good hippy mobile that everyone loves to drive. Of course, I realize most people probably drive it as a status symbol, so when they get home from work, they can rest assured knowing they did their part to save the whales.

  • Jimmerz

    Jimmerz

    #30464970 - 10 years ago

    A couple of things here the article may or may not be taking into consideration:

    Are they counting diesel, which is much more popular and has been for decades in Europe? It struck me when I went to Poland, Sweden, Denmark and Germany, that so many of the cars were diesel. And that they weren't loud and smoky pieces of crap like the infamous diesel passenger cars GM produced. A good portion of European cars are diesel, but this article doesn't mention it once. It's probably not the future of automotive propulsion, but if you are going to compare the two markets it is significant.

    Safety is mentioned. Lack of it in smaller cars. What isn't mentioned is disparity in size among vehicles involved in accidents. If one car is a small, economical one, but statistically the other might be a huge SUV, that makes a big difference. SUVs are not particularly safer, historically they have had more tendency to roll over and such, that's improved over the years. Auto makers have begun designing them so in accidents with smaller vehicles they don't plow up and over. These huge vehicles were never as popular in Europe. So while smaller cars might be safe on their own, the vehicles around them here in America may skew their safety performance downward.

    In reply to breakbread, #2:

    Now, I'm not a physics major or anything, so maybe someone can chime in on this. But I think, once you get to a certain speed, the weight of an object is no longer a penalty when increasing the speed.


    There was a top speed comparison test done by Road & Track many years ago. Ruf Porches and such. It was mentioned in the article that having the added weight of a passenger in the car, while a detriment to acceleration, would have negligible effect on top speed.

  • breakbread

    breakbread

    #30464971 - 10 years ago

    In reply to Jimmerz, #3:

    Yes, America has been very adverse to diesel cars. For whatever reason, a larger percentage of the price of Diesel is federal taxation when compared to conventional gasoline. Because of this, the major car companies don't have the infrastructure in place to offer their diesel vehicles over here. Ford has a 65mpg diesel Fiesta that it won't bring here because they don't feel they could offer it cheap enough due to the costs of shifting production to the states.


    And yes, Jimmerz, that does sound correct about the top speed physics. Of course, mpg figures don't matter, becuase NO ONE really drives in such a way that's conducive to getting the figures that are stated for a given vehicle. I do, because I'm poor and in school and honestly have to make the most of everything. My car is faster than a fucking Prius, but I can't tell you how many times I'm next to a Prius (or any other car like that) at a red light and they fucking BLAST out of the hole when it turns green. I'm by no means put putting along, but I feel like they most certain have to have the pedal near the floor to be accelerating as fast as they are, away from my car.

  • Jimmerz

    Jimmerz

    #30464972 - 10 years ago

    In reply to breakbread, #4:

    There's a bit of history with diesel passenger cars here that probably contributes to their lack of popularity. I mentioned GM making really bad diesel cars, this was back in the late seventies and early eighties. These cars were bad even by the standard of crap cars we were producing at the time. (Talking Vega, Pinto, Chevette, Pacer. That's a very low standard.) GM didn't design a diesel engine. They attempted to strengthen the block of a gas engine for the higher compression. The result was a noisy, smoky, totally unreliable heap of junk. My neighbor had a Buick with one of these engines. It sounded like a helicopter on the rare occasions it wasn't in the shop for repairs.

  • Tb0ne

    Tb0ne

    #30464973 - 10 years ago

    In reply to quazz4life, #1:

    Most battery cars have a range of about 40 miles, which for most people should be enough to get too and from work and run a few errands. I really like a Volvo concept in which it could go ~40-50 miles on a battery charge and a small diesel generator would kick in if you needed to go father.

    In reply to Jimmerz, #3:
    In reply to breakbread, #2:

    The weight of the car and the safety are strongly tied together. You need the energy consuming capability of the metal which is why you can't cut weight with carbon fiber. Metal will deform which will soak impact stress. A brittle carbon fiber or ceramic will just snap and the impact will be far more violent.

    In reply to breakbread, #4:

    I absolutely HATE Prius's. The take far more energy in manufacturing and extra machining and complexity than is necessary. There are far better solutions out there in my opinion. They're being hailed as a savior but really their nothing more than a band-aid. My fear is that people will be satisfied with it as a solution and just sit back and do nothing. I'm strongly eying the new Subaru Forester with the 4 cylinder boxer diesel as a far better alternative.

    Ultimately I like the Volvo concept I mentioned earlier. A series hybrid rather than a parallel. Rather than have the electric motor dump into the drive shaft which is horribly inefficient, you use a diesel generator to supply power to motor's at each wheel hub. Rather than lose efficiency through each single mechanical piece of a drive train you get negligible wire loss along with an over 90% efficiency of an electric motor that has a linear power band. That is the fucking way to do a hybrid in my opinion. Combine it with biodiesel or maybe even a fuel cell and you got the way to go. Battery tech is gonna take to long to catch up methinks, what not use what we already know?

    Post edited 6/30/09 3:32AM

  • breakbread

    breakbread

    #30464974 - 10 years ago

    In reply to Tb0ne, #6:

    Carbon fiber is stronger than steel when used appropriately; it's just expensive to manufacture right now.

    And yes, I agree about the Volvo and also the Chevy Volt. A lot of people are knocking the Volt because they electric motor will only carry you some 40 miles before switching over to gas. However, as you said, 40 miles is all most people need on a typical day.

    Also, it's worth mentioning that the Audi R8 V12TDI gets like 24 mpg while making 500hp and 738lb-ft.

  • Tb0ne

    Tb0ne

    #30464975 - 10 years ago

    In reply to breakbread, #7:

    It still is a matter of distortion energy versus tensile strength. In an impact metal will deform, dissipating energy. Think of a spring, but stretched far enough to permanently deform it. Carbon fiber will snap which will not dissipate any energy. Carbon fiber is stronger but will store far less energy.

  • breakbread

    breakbread

    #30464976 - 10 years ago

    In reply to Tb0ne, #8:

    Interesting. I wasn't aware of that, honestly.

  • Taketoshi

    Taketoshi

    #30464977 - 10 years ago

    In reply to breakbread, #9:

    because you are not a SCIENCE!tist like paul is

    nub

  • SupaChurchFn

    SupaChurchFn

    #30464978 - 10 years ago

    This sort of discussion pops up every once in a while, and I end up always having the same train of thought- although technology advances for the cars we use to make them more fuel efficient and responsible, I feel like we also need to change our usage habits. As a college student, I'm able to walk everywhere in town easily- the only time I drive is when I need to transport something too heavy or awkward to carry. I know that's not reasonable for most people. However, I see people like my parents: they decide they want to buy something, hop in the car, drive to the store, buy whatever it is, then drive home. At least for my family, I think we could cut down a lot on spending (both in gas and impulse purchases) if we really stuck with the whole shopping list concept and consciously pared our shopping trips down to once a week- that way that impulse new desk lamp or computer mouse may end up falling off the list anyway, and we won't make four trips to the store to purchase four items.

    My thought/question is- is it more gas/transport efficient to purchase online? While it saves individual households gas money, does it create more oil dependency to have things delivered?

  • breakbread

    breakbread

    #30464979 - 10 years ago

    In reply to lonegirl, #11:

    Considering that courier services is a business, it's in their best interest to be as efficient as possible. What was the story from a few years back where UPS was changing all their routes to minimize the amount of left turns their drivers would encounter? In any case, their job is to maximize the packages delivered and minimize their own expense in doing so.

  • dark54555

    dark54555 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    #30464980 - 10 years ago

    My IS250 gets over 30 mpg on the highway and it has a V6.

    But the Jetta TDI is already getting over 40 mpg and actually drives like a real car rather than like an overgrown golf cart...

  • quazz4life

    quazz4life

    #30464981 - 10 years ago

    In reply to dark54555, #13:

    My little Kia Rio gets 35mpg highway.
    but it's just a little fourbanger.

  • dark54555

    dark54555 FIRST Member Star(s) Indication of membership status - One star is a FIRST member, two stars is Double Gold

    #30464982 - 10 years ago

    I just realized that came out a little weird. My IS doesn't drive like a golf cart either. Hybrids do. And they all drive like shit.

    Find me a hybrid that drives like a real car, and I'll believe in the tech.

  • Tb0ne

    Tb0ne

    #30464983 - 10 years ago

    In reply to dark54555, #13:

    Subaru Forester - Diesel Boxer

    ^

    Car I'm buying after I get out of grad school. 50 MPG

  • breakbread

    breakbread

    #30464984 - 10 years ago

    Ah, the boxer. I swear to christ/buddah/raptor jesus, Porsche better not source an inline 4 for a future Boxster. Because they're fucking talking about it.

    /of topic.