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What is "wrong" with these new subcompacts?

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Comments

  • bumpybumpy Posts: 4,435
    The gravest danger of underpowered cars is (in my experience) when you find yourself stuck in the right lane of a freeway (say behind a vehicle that has suddenly slowed down too much) and then trying to merge in to the next lane to the left when you yourself are stopped or nearly stopped.

    That's a bad idea no matter what you're driving. If the speed differential is more than 20 mph or so, you shouldn't be lane jumping in the first place.
  • Granted, but what do you do? Sit there and eat a sandwich and dial 911?

    sooner or later you gotta make your move.
  • bumpybumpy Posts: 4,435
    It's not that big of a deal. If traffic is just slowing down, it will get going again before long. If traffic stopped completely and stays that way, there is a good reason for it and you can drive around that reason on the shoulder.
  • I'd rather shred rubber and get out of there! :shades:
  • kreuzerkreuzer Posts: 113
    cars be safe (Example: escape severe injury or death) if it was at a dead stop and a large truck, SUV or other, rear ended it going at a high speed say 40+mph?
    I'm just curious to see what others who know the laws of physics much better than me think.
    What about large cars under the same conditions? I understand the more metal that you have between the occupant and the other car increases the odds but really by how much?
  • The dynamics of accidents are too complex to predict any outcome based on size or weight. You could be in an Abrams tank and still get a rear view mirror imbedded in your head, or other freakish thing.

    Race cars are among the lightest and smallest vehicles on earth and people survive 200 mph crashes in them.

    People always counter-argue "Yes, but all things being equal, a big car is safer" but even that doesn't wash.

    Accidents are too complex and unpredictable, and that's why despite huge technological advances, we still lose 43,000 people a year to them.

    I'd say that a mandatory 1 month jail term for not wearing a seat belt would save far more lives than heavier cars with armor plating over them.
  • andre1969andre1969 Posts: 21,584
    ars be safe (Example: escape severe injury or death) if it was at a dead stop and a large truck, SUV or other, rear ended it going at a high speed say 40+mph?

    Well, a rear-end collision is a totally different dynamic from a front-end collision. In this case, one of the most important factors could very well be how well-designed your seats are. A big car with crappy seats (too low, poorly designed headrests, etc) might hurt you more than a little car with well-designed seats. Now as a result of the impact, the smaller the car, the more easily it's going to get thrown forward at a greater speed, so you have to take that into account. Now if you have, say, a Scion xA and a Lincoln Town car, and the vehicle doing the rear-ending is an Expedition, the heavier Town Car won't get pitched forward nearly as brutally as the xA. But if it's a Greyhound bus, dump truck, or tractor trailer doing the hitting, the extra bulk of the Town Car is probably negligible.

    I forget all the nuances of the physics behind deceleration and such, but I do remember that if you have two 4000 pound cars hit head-on at 50 mph, they should stop dead. So basically, each driver decelerated from 50 to 0 instantly. However, if a 4000 lb car doing 50 mph, a 2000 lb car coming the other way would have to be doing 100 mph for the impact to cancel out and the cars to both stop dead. So in this case, the 4000 lb car decelerated from 50-0 instantly, whereas the 2000 lb one has to decelerate from 100-0...a much more brutal force.

    Anything less than 100 mph, and the result is that the 4000 lb car doesn't get totally stopped, but is still moving in its original direction, whereas the lighter car has not only been stopped from moving forward, but has actually been thrown backward.

    Of course, this is all theory, and doesn't take into account the energy absorbed in crumple zones, friction of the tires, gravity, etc.

    Oh, another problem with trucks, SUVs, etc, is that they tend to sit up higher, so when they hit you, they override your bumper and come into contact with the much more vulnerable parts of your car. So they can often mess up any car, no matter how big it is. Years ago, there was an accident in Baltimore where someone was in an OJ style Bronco, trying to run from the cops. He hit a '95-96 style Caprice copcar, head on, at some ridiculous speed. The Bronco pretty much ceased to exist from the firewall forward. The Caprice? Pretty much obliterated back to the C-pillar, as the Bronco over-rode it and basically stripped the body from the frame. The police officer was killed instantly, while the Bronco driver just suffered bruises and scrapes.
  • ateixeiraateixeira Posts: 72,587
    So I parked facing it, just to see the contrast.
  • bumpybumpy Posts: 4,435
    cars be safe (Example: escape severe injury or death) if it was at a dead stop and a large truck, SUV or other, rear ended it going at a high speed say 40+mph?

    Sure. One woman I know with a Toyota Matrix got rear-ended by a Toyota pickup going about 60 mph. The Matrix was totaled since the unibody bent behind the front doors, but she came out with nothing worse than some soreness from the seat belt. A bigger vehicle would have just pushed the Matrix farther forward.
  • andre1969andre1969 Posts: 21,584
    A bigger vehicle would have just pushed the Matrix farther forward.

    That probably depends on the speed that the car gets hit. For example, if you hit it with another Matrix at 10 mph, or I ran into it with my pickup at 10 mph, the damage would probably be about the same...even if I just kept my foot on the gas and kept pushing that Matrix along at 10 mph indefinitely.

    Once you get up into higher speeds though, the heavier vehicle is going to hit harder. Now eventually, there probably gets to a point any extra weight doesn't matter. For instance, getting hit by a 200 ton locomotive at 60 mph, it doesn't matter if it has a few thousand tons of train behind it or not!
  • The goal of a vehicle in a collision is to absorb force to prevent passing it on to the occupants. There are very few "perfect" collisions the real world. Cars hit things and bounce and spin or flip and roll or what not.
    Vehicles being physically pushed forward in a rear end crash isn't exactly a terrible thing, as it allows the force to be dissipated over a greater distance and time. Head on collisions usually aren't 100% head on, leading to the frontal offset crash tests. If you watch that test, both cars usually end up spinning as they dissipate force. Front and back collisions are also better than t-bone type collisions because of the distance between your butt and the point of impact. In a front or rear collision, the point of impact is 5-6 feet away, where as a side impact is 5-6 inches away.That is why side air bags are important.
  • robertsmxrobertsmx Posts: 5,525
    Its funny... the Smart's height makes it look bigger than the PT Cruiser behind it.
  • tiff_ctiff_c Posts: 531
    The dynamics of accidents are too complex to predict any outcome based on size or weight. You could be in an Abrams tank and still get a rear view mirror imbedded in your head, or other freakish thing.

    LOL! :D
    Now I'd love to see an M1A2 Abrams with a rearview mirror! hahaha. That would be priceless! :D

    Regarding the other comments. If I have to be rear ended I'd rather be in a 65 ton Main battle tank than say a subcompact car or even a Semi!
    Yeah you'd feel the tank move a bit if a Semi hit it doing 40+mph but the 1500HP engine would be murder on fuel economy considering it can seat only 4 people.
  • imidazol97imidazol97 Crossroads of America: I70 & I75Posts: 17,699
    >Vehicles being physically pushed forward in a rear end crash isn't exactly a terrible thing, as it allows the force to be dissipated over a greater distance and time.

    The fact that the one vehicle ends up being accelerated in a forward direction isn't the real key here; it's the amount of crush involved in both the impactor and impactee vehicle that occurs and dissipates some of the kinetic energy of the impactor relative to the impactee's speed that determines the acceleration on the impactee vehicle's occupants. That acceleration rate is what relates to injury as well as the design of the car seat and head rest.

    If the vehicles are both stiff frame with solidly mounted bumpers, the acceleration on the impacted vehicle and the deceleration on the striking vehicle will be much more rapid causing more injury.

    I watched a Saturn rear-ended by a Cobalt a couple of Saturdays ago. The Saturn started to bend behind the rear wheels to allow the rear end to crush more without accelerating the occupant cage as much. The Cobalt deteriorated back to the motor absorbing lots of energy in bending and crushing metal and parts.

    This message has been approved.

  • I guess I should have said "periscope" :blush:

    I've driven a tank but not an Abrams. I do fantasize about stealing one and letting it rip on Highway 17 out of Santa Cruz. Sure, I'd spend a lifetime in jail (maybe two) but it would make a statement to Caltrans. And I would get to San Jose faster in rush hour.
  • plektoplekto Posts: 3,706
    What I noticed with the discussion on merging and acceleration is two things:

    - Automatic.
    - Automatic.

    I can take my old 1987 4Runner and merge just fine in L.A. because I have a manual gearbox and 3rd gear gets me going quite quickly from 40-60mph. Downshift and floor it - zoom - I'm gone. In a slush-o-matic, well, yeah, you need gobs of HP and Torque because you're always running at 1/2 optimal efficiency.

    Lug lug lug - STOMP. Gosh - nothing happened!

    DUH.

    The manual in the Smart is a clutchless manual like Mercedes used to make in the 60s. Technically it's a manual with solenoids and computer activation of the clutch. So it will downshift quite quickly, and it's QUICK if you drive it aggressively in manual mode because it has a good torque to weight ratio. 20-40mph in traffic is a cinch. 0-60 requires holding it in gear until 3/4 of redline, but it's fine - certainly no worse than a typical Buick or Camry made ten years ago.
  • grbeckgrbeck Posts: 2,361
    Mr. Shiftright: I've driven a tank but not an Abrams. I do fantasize about stealing one and letting it rip on Highway 17 out of Santa Cruz. Sure, I'd spend a lifetime in jail (maybe two) but it would make a statement to Caltrans. And I would get to San Jose faster in rush hour.

    On one of those police chase video shows, I remember a man did just that with a tank in the San Diego area. He rampaged through a residential neighborhood, running OVER parked cars, trucks and even a motor home. He got the tank stuck on a freeway divider, and the police were able to get on the tank and eventually shot and killed him. So I wouldn't recommend this...
  • how 'bout if I just weld a snowplow attachment onto a Ford dually? :shades:
  • how 'bout if I just weld a snowplow attachment onto a Ford dually?

    You silly bay area folks...you don't have to weld anything, here in Michigan at Varsity Ford they have a number of Superduty Ford trucks with the snow plow prep already installed and ready to go. You just add your Myer blade and hydraulics and you are all set.

    This way you can angle the blade from inside the cab, so as you push the cars out of your way, you can alternate right or left.

    :cry: I miss the central coast. I wanna go home. :cry:
  • boaz47boaz47 Posts: 2,730
    With 0-60 times as slow as posted here for the Smart your definition of quick needs some explaining. If the xA and xB were condemned for being slow it is hard to believe the Smart that is even slower would be considered quick. After all when the run the 0-60 tests they are trying as hard as they can to get the best times.

    Still many of the post in this discussion have reached back into the minds of many of us to express the concerns that most US consumers have. If we are going to buy a sub compact how will it hold up to an impact with the millions of bigger vehicles we see on the road every day? I agree that no one plans on having an accident but they do happen. While any accident would cause us to clinch our teeth in expectation it is easy to see how most people might look at getting hit by the neighbors 18 year old son driving a F-150 when you go through an intersection in your new Smart.

    I agree with Shifty that we need to study more to see why small car deaths are going up when the total death rate for new vehicles are going down. There could be any number of reasonable explanations. But your brain tells you that if you are given the choice of getting hit by a Smart car or a Expidition you aren't going to pick the Expidition and pull for some freak set of circumstances to save you.

    And Shifty, there have been times when I might have decided to put a plow on the front of my Old Ram Charger when I was commuting. But an extra heavy duty Brush guard did just the trick one afternoon. My wife was driving a friend to the post office when a Grand Am ran head on into her coming around a slippery curve. My Wife saw the Grand Am coming and managed to pull as far right as she could and stopped. The Grand am hit just to the left of our front license plate and dead on into the front bumper and brush guard. We drove the Ram Charger home and later had it fixed getting a new bumper, replaced the drivers side fender and stearing box. They just cleaned an re polished the brush guard. They had to bring in a flat bed to haul the Grand Am away. I do some off roading so I believe in body armor. I haven't added much to the GMC but there are times I have considered it.
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