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0-60 is so yesterday! - READ ONLY

154 messages,  Last post on Oct 09, 2007 at 11:40 PM

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Messages Page 13 of 16

#115 of 154 Re: Also consider 0-100 mph [andres3] by blufz1

Jan 26, 2007 (8:28 pm)

Replying to: andres3 (Jan 26, 2007 5:00 pm)
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.

#116 of 154 Re: other testing and information. [habitat1] by readerreader

Jan 26, 2007 (11:15 pm)

Replying to: habitat1 (Jan 26, 2007 4:22 am)
"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.

#117 of 154 5-60mph times by lobe

Jan 27, 2007 (12:23 am)

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).

#118 of 154 Re: 5-60mph times [lobe] by robertsmx

Jan 27, 2007 (8:46 am)

Replying to: lobe (Jan 27, 2007 12:23 am)
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.

#119 of 154 Re: Horsepower, Torque, and Gearing [wale_bate1] by cobraboy1

Jan 27, 2007 (1:28 pm)

Replying to: wale_bate1 (Jan 26, 2007 10:54 am)
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.

#120 of 154 Re: Horsepower, Torque, and Gearing [cobraboy1] by wale_bate1

Jan 27, 2007 (2:29 pm)

Replying to: cobraboy1 (Jan 27, 2007 1:28 pm)
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?

#121 of 154 Torque Vs. HP by andres3

Jan 27, 2007 (7:26 pm)

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.

#122 of 154 Re: Torque Vs. HP [andres3] by robertsmx

Jan 27, 2007 (8:34 pm)

Replying to: andres3 (Jan 27, 2007 7:26 pm)
In addition to your earlier argument about torque being the thing, you're throwing in a comparison of perhaps a normally aspirated 2 liter motor from Honda to a six cylinder engine from a German automaker. If it were just Honda versus German car, explain this (from a C&D comparison):
2002 CL-S 6MT / 2002 330i 6MT
0-60: 5.9s / 5.8s
5-60: 6.2s / 6.5s
 
So, the Acura didn't do as well as the BMW in 0-60 but it did better in rolling start. Hmmmm...
 
As for the original point, I will repeat, torque is only as good as the HP it translates to. If you can prove it otherwise, I will look forward to learning something new.

#123 of 154 0-60 by heffling

Jan 29, 2007 (12:09 pm)

Zero to Sixty to me is a representation of the entire package of a vehicle. The most representative 0-60 would of course be from idle, with no clutch drop or any other fancy tricks. Otherwise, this just puts car magazines in the same category of misrepresentation that they have accused the EPA of being in.
 
Realisitically, the dyno curves of a vehicle, showing torque and rpm (hp comes right out of these), acts only as an evaluation of the engine. The gearing differences between vehicles such as transmission and rear axle gearing are not included in such an evaluation. Neither are factors such as a suspension and tire's ability to put the power to the pavement.
 
A 0-60 run (or 0-100 or whatever) do give an idea of such information. My personal preference is for 0-60 due to the fact that typically I don't drive much over 70 anyway (legal limits and all). Also, some cars will not go above or at least very far above 100 mph, and will suffer accordingly at the high end. Think especially of some of the subcompacts coming out of europe and asia.
 
It is very possible to gear a vehicle such that it will have an extremely fast acceleration at low and mid speeds (under 80mph), but will bog down at higher speed. Because of this, I feel it is best to look at a range of 0-x times, similar to what was posted previously, where you have
 
0-30
0-40
0-50
0-60
etc
 
This will give a much better view of the overall acceleration performance of a vehicle.
 
However, that being said, I feel that most consumers prefer to look at simple statistics without having a deeper understanding of the meaning behind them. For your average consumer, I feel that a 0-60 time (again, with no clutch dump) is a very good evaluation tool. Your average driver, after all, spends 90% or more of their acceleration time at speeds less than 60 mph. And even more of their "hard" acceleration at lower speeds.
 
So, just because 0-60 isn't the best way to evaluate the performance of a vehicle, that doesn't make it an invalid way of making a comparrison.

#124 of 154 Re: 0-60 [heffling] by robertsmx

Jan 29, 2007 (2:49 pm)

Replying to: heffling (Jan 29, 2007 12:09 pm)
I don’t think the primary point is about usefulness (or lack of) 0-60 test. It is over-emphasis on that metric when it comes to publications, and the way it is determined.
 
Automotive reviewers need to consider more realistic situations, including 0-60, by throwing in test scenarios involving rolling acceleration. Sometimes I just find it funny to see 0-20 or 0-30 acceleration time. And then, there are some reviewers that go beyond 0-60 and do include something more meaningful (5-60) and mess up elsewhere (30-50 and 50-70 in top gear only if manual transmission). Be it Edmunds, R&T, C&D… they are all guilty. CR does one of the few things well, and it happens to be this.
 
And I liked what I saw in an Autoweek review. They published, not only 0-60 times, but also 20-40, 40-60 and 60-80 mph acceleration runs. However, even after all that, the only one of these that gets mentioned is 0-60. Oh well…

Messages Page 13 of 16

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