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0-60 is so yesterday!

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  • robertsmxrobertsmx Posts: 5,525
    what is a typical first or second gear ratio these days?

    Choice of gear ratio is largely dependent on what overall ratio engineers strive to achieve. If I had to take a guess, I would say a typical 5 speed automatic transmission will have an overall drive ratio of about 12.00:1 in the first gear. That can be achieved using a 3.00:1 axle ratio to go with 4.00:1 first gear ratio, or using a 4.00:1 axle ratio to go with 3.00:1 first gear ratio. The second gear is generally 40-45% taller than the first.

    And, generally, the overall span for a 4 or 5 speed transmission is 4.5-5.0 (overall span = first gear ratio divided by fifth gear ratio). So, a typical 5-speed auto (or manual) may have the following gear ratios to go with 4.00:1 axle ratio -
    Gear 1- 3.00:1 (overall drive ratio- 12.00:1)
    Gear 2- 1.80:1 (overall drive ratio- 7.20:1)
    :
    Gear 5- 0.65:1 (overall drive ratio- 2.60:1)

    In a typical 6-speed auto transmission, emphasis has been on increasing that span to about 6.0 or better. This tends to allow shorter low gears and a more relaxed top gear. In fact, many 6ATs have overall ratio in first gear of over 16.00:1 (that is how BMW's generally provide feel of being more powerful from lower rated power).
  • andres3andres3 CAPosts: 5,278
    I think this gives the best indication of how powerful a motor is, with the most consistent results. Plus, no one drives 60 MPH anymore, 70 is a better highway freeway speed.
  • robertsmxrobertsmx Posts: 5,525
    Well, 0-70 is no better or worse than 0-60. Besides, most cities have 60 mph speed limit on freeways, where you're most likely to use a 5000 rpm "launch" from 0 mph. :D
  • andres3andres3 CAPosts: 5,278
    Then why not standardize the rules. Just make the standard that you can't have any time to do anything other than start the car and have it at idle. Therefore, no revving, no prepping the launch. Just start from idle, any time you spend trying to rev up your launch, is time that is part of your 0 to 70 or 0 to 60 time. I like 70 more because virtually no car will get there without at least 2 shifts, whereas 60 might be obtainable in 2nd.
  • robertsmxrobertsmx Posts: 5,525
    Its more logical to expect more realistic runs incorporated in road tests than one that is flashy. But magazines want flash! There is no excitement when you see 0-60 runs posted in Consumer Reports.

    In fact, I'm not opposed to 0-60 runs the way magazines do it. Let them! It does make for a good reading. But IMO, more realistic tests should also be incorporated.
  • wale_bate1wale_bate1 Posts: 1,986
    I think the mags often do their readers a disservice with the tests. It's not the test itself, but the presentation.

    From an Autoweek article on Aura v. Camry: "On the track, the Toyota drew first blood. From a standstill to 60 mph, the Camry clocked a best time of 6.22 seconds, 0.33 faster than the Aura’s 6.55, no doubt hampered by its extra 164 pounds of mass." Hello? .33 seconds is drawing "first blood"?
    :sick:

    No wonder the unwashed think 0-60 means more than it does...
  • john_324john_324 Posts: 974
    The problem with the auto mags is that for almost all of them, the mindset is driven by either:

    A bunch of testosterone-fueled middle-aged men who found a way to turn their racecar-driver fantasies into a paying job,

    or

    A collection of scolds who'd really rather people took public transportation, but if they *must* have a car, they should buy something that would make a government bureaucrat happy.

    I wish there was "Real-world Automotive Fun" magazine... :)
  • saabgirlsaabgirl Posts: 184
    If you can find a typical salesperson on any given Wednesday on any average car lot who could even come up with the correct 0-60 time for the model about which you inquire, I'll buy a new hat and eat it!

    Fortunately, this nugget of information is readily available from other sources on any model I'd be interested in, so I'd already know the answer. It seems to me that 0-60 is so much a part of automotive nomenclature that I'm surprised people seem to be suggesting that it can't be answered without reference to torque curves and other technical jargon.
  • wale_bate1wale_bate1 Posts: 1,986
    I think you're making a valid point. I believe our fellow techno-motor-geeks in here are simply suggesting there are more complete ways to evaluate performance on paper.

    My thought is that all the paper in the world won't give you the real story. Certainly I've experienced cars with numbers that don't look competitive, but that had it all over the competition on the road...
  • wale_bate1wale_bate1 Posts: 1,986
    "Fortunately, this nugget of information is readily available from other sources on any model I'd be interested in, so I'd already know the answer."

    That was kind of my point - you probably know more hard info going in to the dealership than you can get there. ;)
  • habitat1habitat1 Posts: 4,282
    Although I don't believe that straight line acceleration is the most important factor in "performance", when I do want to get a feel for waht to expect in a test drive, I might consider 0-100 times more relevant than 0-60 times.

    The differences in 0-60 acceleration can often appear not that significant - under 4.5 seconds is very fast, 5.5 seconds is average for a sports car, 6.5 seconds is my 1995 Nissan Maxima SE 5-speed, 7.5 seconds is SUV territory. Add to that that "launch" techniques, different testing methods and manufacturer conservatism (or not) can lead to fairly large variances, and you do have to be careful about concluding too much. For example, my 911S is rated conservatively by Porsche at 4.6, tested by the three mags at 4.3, 4.2 and 3.9.

    One of the mags lists 0-100 times. They tell me a lot more about the true acceleration performance. Not because I try to replicate that in my daily driving, but because it takes out some of the testing variation, it is a good surrogate for passing power, and it really separates the men form the boys. 0-60 vs. 0-100 times for three of my current/past cars.

    2005 911S 0-60: 4.2s 0-100: 10.1s
    2002 S2000 0-60: 5.5s 0-100: 13.9s
    1995 Maxima 0-60: 6.6s 0-100: 20.5s

    So, as you can see, although only 2.4 seconds in 0-60 separates a 12 year old family sedan from a current model serious sports car, the difference expands to 10.4 seconds going to 100 mph.

    As if this gang needed more numbers to consider. ;) I still think that my Honda S2000 was arguably about the most fun one could have under $60k because of its go-cart like handling. I've never seen a true quantification of that. It's not just lateral g's or slalom. The car just felt spectacular through my favorite stretch of Rock Creek Park. Damn close to as good as my three times as expensive 911S. And way better than a business associates Corvette that is just as fast as the 911, but feels big, stiff and bulky through that stretch of road.

    Ultimately, every buyer should put their rear end in the seat for an extensive test drive, no matter what the published numbers and reviews say.
  • andres3andres3 CAPosts: 5,278
    So maybe 0-60 is too short a period to judge, but maybe 0-100 is more than is necessary to get the best idea of performance in a straight line.

    Why not settle in the middle and use 0-80 MPH times? This way, you don't get too carried away, but you do lessen the variations in performance.
  • habitat1habitat1 Posts: 4,282
    Because 0-100 is already readily available by at least 1 magazine.
  • blufz1blufz1 Posts: 2,045
    There are 2 benchmarks in virtually every complete road test,0-60 and 1/4 mile time and speed. They are sufficient for the average person. Most car buyers don't even know these #s,much less care. So relax about the benchmarks.
  • "The first thing I'd conclude (leaving aside the question of the mysterious extra cam in the 'vette's engine" )

    I am guilty of a misprint, the Corvette engine is listed as "OHC" vs the 911's "DOHC". I'm not an engineer, I take it that "OHC" and "SOHC" are not the same?

    "Unless the Corvette is wheel-hopping badly or suffering from inordinately high drivetrain losses, it should be able to dispatch the Porsche."

    I think you nailed part of the answer. In spite of massive rear tires on the Corvette, the 911, even in RWD form, is far more effective in putting it's power to the pavement. The pictures show a lot of tire smoking on the Corvette, with the 911 sling-shotting out of the start. Unfortunately, American performance cars are still designed with an approach that over-emphasizes "quantity" - hp, torque, tire size - than "quality" in the form of cutting edge dynamic engineering.

    Good thing that's not the case with Boeing and airplanes, or they would be the GM of the airplane business instead of the world leader.
    -------------------------


    Good thing I am here to set the record straight!

    1. All Porsches are good at acceleration because they are rear-engined. That means the weight of the engine sits atop the rear axle--contributing to grip off the line.
    That also means that they are prone to oversteer.
    "Even in RWD form"?
    Please! In both configurations it has an acceleration advantage.

    2. If it's the GT3, it's even more at an advantage, because it has racing slicks on. The Corvette have everyday run-flats because it is a car that is used every day.

    It has nothing to do with "dynamic engineering", "flux capacitors" or the like.
  • lobelobe Posts: 10
    If one wanted the most "realistic" times, with realistic being defined as how most people would actually drive their car, it would be the 5-60mph acceleration times. I usually only read Car and Driver, so I don't know if the other magazines tend to include those.

    There is a reason they put that measure in. It eliminates what a skilled driver can do with the car while it is still sitting at zero mph getting ready to go. If it is an automatic transmission vehicle, they will stand on the brake while accelerating the engine to whatever rpm they can that, when they let go of the brake, they don't spin the wheels. That will give them the fastest launch and the fastest 0-60 times. It is the RARE driver that is going to do that to their own care very often.

    If it is a manual transmission, they will rev the engine to whatever rpm they can (without spinning the tires when they let the clutch out), and then dump the clutch. It makes for a great looking 0-60 time. But do that in real world driving from a lot of stops. See how long your clutch lasts.

    This kind of behavior favors cars that may have a lot of horsepower, but not as much torque. Someone mentioned their Honda S2000. Great power at high rpm's. Not a lot at low rpm. Great 0-60 time. Good 5-60 time. Mazda Rx-8. Same thing. Great 0-60 time. Good 5-60 time. Same with turbo engines, like my old Saab 900 turbo, or like the Mazdaspeed 6.

    In real world driving, starting the measurement at a rolling 5 mph start eliminates those "optimizing" techniques that RARELY are done in "real world" driving. So those times probably gives the majority of drivers a better comparison of what a car will "feel" like when they are accelerating.

    But 0-60 times are way more available, and get you at least in the ball park of what certain cars do, and are somewhat fun to follow. Just need to keep them in perspective.

    Similarly, people love to look at horsepower numbers. When for driving in the U.S., for most people, torque numbers would be more likely relevant.

    0-60 and 0-100 and 1/4 mile times are fun comparators. 5-60 mph times, in my opinion, are most helpful as a "real world" comparison (albeit less available).
  • robertsmxrobertsmx Posts: 5,525
    I agreed with you completely, until you said this...

    Similarly, people love to look at horsepower numbers. When for driving in the U.S., for most people, torque numbers would be more likely relevant.

    Torque is only as good as the HP it translates to. In the end, HP wins. Torque numbers by themselves are useless.

    Having said that, I just noticed, reading a Camry and Aura comparison, that AutoWeek includes rolling acceleration. Note these numbers:
    0-60: Camry (6.2s), Aura (6.5s)

    Looking at 0-60, there isn't a meaningful difference between the two cars. Now, here things get interesting:
    60-80: Camry (4.3s), Aura (5.4s)

    60-80 acceleration would be most important in overtaking situations on 2-lane highway. And the difference between the two is 1.1s.

    Those are the kind of acceleration numbers that need to be a part of any road/comparison test.
  • If you can find a typical salesperson on any given Wednesday on any average car lot who could even come up with the correct 0-60 time for the model about which you inquire, I'll buy a new hat and eat it!

    I'm a sales person, ask me a 0-60 time on any car.
  • wale_bate1wale_bate1 Posts: 1,986
    Cobraboy my new friend, that makes you about as atypical as they come!

    I will say that when I test drove the IS350, all the salespeople knew the 0-60. Mostly I believe it's because there's little else on which to make an IS350 sale, IMO.

    What do you sell?
  • andres3andres3 CAPosts: 5,278
    I've never heard a good explanation either way for which one is more important. In driving a Honda and a German car now, i'd say the wider power band of the german car is what really makes the difference, though if you can keep your Honda in the high rev's, its gonna be faster. If you start from idle you'll be left in the dust.
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