Are there any 981 Spyder reviews that show performance #s. 0-60, Lateral G, 1/4 mile.
06-14-2016, 10:47 AM
#16
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^^^^^ Good catch. Seems like an error as logic dictates a rolling start would generate a quicker time to 60 than a standing start. I went back and double-checked the article, but this is what Car & Driver has reported. 
Some info on how C/D test cars from:
http://www.caranddriver.com/features...braking-page-2
"In a manual-transmission car, we usually start acceleration runs with a wheel-spinning launch. It's simple: The engine is revved to a high rate, and the clutch is abruptly engaged. No power shifting or speed shifting is allowed, so we shift rapidly but by the everyday method of disengaging the clutch and lifting off the gas. With a great variety of vehicles, it's not always readily apparent which is the optimal launch technique, but we do our utmost to extract every ounce of speed from each one. Often we try launching the cars at varying rpm while hoping nothing breaks.
On most cars, we upshift at the engine's redline, but on torquey engines, we experiment with short shifting as well. With automatics, we try shifting manually if the transmission upshifts short of the redline.
. . . .
Since most owners will seldom subject their cars to brutal launch techniques, we also perform what we call a street-start acceleration test from 5 to 60 mph. While rolling with the car in gear, we floor the accelerator at 5 mph and shift quickly at the optimal shift point."
Some info on how C/D test cars from:
http://www.caranddriver.com/features...braking-page-2
"In a manual-transmission car, we usually start acceleration runs with a wheel-spinning launch. It's simple: The engine is revved to a high rate, and the clutch is abruptly engaged. No power shifting or speed shifting is allowed, so we shift rapidly but by the everyday method of disengaging the clutch and lifting off the gas. With a great variety of vehicles, it's not always readily apparent which is the optimal launch technique, but we do our utmost to extract every ounce of speed from each one. Often we try launching the cars at varying rpm while hoping nothing breaks.
On most cars, we upshift at the engine's redline, but on torquey engines, we experiment with short shifting as well. With automatics, we try shifting manually if the transmission upshifts short of the redline.
. . . .
Since most owners will seldom subject their cars to brutal launch techniques, we also perform what we call a street-start acceleration test from 5 to 60 mph. While rolling with the car in gear, we floor the accelerator at 5 mph and shift quickly at the optimal shift point."
06-14-2016, 12:21 PM
#18
Intermediate
No, it is normal that the rolling start 5 to 60 measure will be a bit slower than the "launch" from 0 to 60. In that test, the car will be launched from several thousand rpm, which will instantly (or far more quickly) get the car to the heart of the power curve. That is more than enough to make up for the 5mph headstart in the rolling test, in which the driver will floor it while moving and the car in gear, at a speed at or just above idle; it is going to take the better part of a second for the engine to get where the power is.
06-14-2016, 04:09 PM
#19
No, it is normal that the rolling start 5 to 60 measure will be a bit slower than the "launch" from 0 to 60. In that test, the car will be launched from several thousand rpm, which will instantly (or far more quickly) get the car to the heart of the power curve. That is more than enough to make up for the 5mph headstart in the rolling test, in which the driver will floor it while moving and the car in gear, at a speed at or just above idle; it is going to take the better part of a second for the engine to get where the power is.
06-14-2016, 04:20 PM
#20
Intermediate
At 5mph, the car is just off idle and the power peak is well over 6000rpm, so not a lot of that power is available that low.
Compare most of their 50 to 60 tests and you'll see similar results, especially for a car like this: with long gearing in the lower ratios and a comparatively peaky, normally aspirated engine. The Cayman GT4 yielded the same sot of result: 4.1 sec from 0 to 60, and 4.7 sec in the 5 to 60 test. New Camaro SS: 0 to 60 in 4.0 and 5 to 60 in 4.8, just to pick a couple of relevant examples. And the Camaro certainly isn't as peaky as the Porsches, though it is pretty long-legged too.
If they screwed up a shift I assume the delta would probably be even larger; but they'd simply re-do that test, not publish bad data - most testers will do many runs to ensure they got the best possible result; the abuse the test cars go through is amazing sometimes....
Compare most of their 50 to 60 tests and you'll see similar results, especially for a car like this: with long gearing in the lower ratios and a comparatively peaky, normally aspirated engine. The Cayman GT4 yielded the same sot of result: 4.1 sec from 0 to 60, and 4.7 sec in the 5 to 60 test. New Camaro SS: 0 to 60 in 4.0 and 5 to 60 in 4.8, just to pick a couple of relevant examples. And the Camaro certainly isn't as peaky as the Porsches, though it is pretty long-legged too.
If they screwed up a shift I assume the delta would probably be even larger; but they'd simply re-do that test, not publish bad data - most testers will do many runs to ensure they got the best possible result; the abuse the test cars go through is amazing sometimes....
06-17-2016, 02:56 AM
#21
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No, it is normal that the rolling start 5 to 60 measure will be a bit slower than the "launch" from 0 to 60. In that test, the car will be launched from several thousand rpm, which will instantly (or far more quickly) get the car to the heart of the power curve. That is more than enough to make up for the 5mph headstart in the rolling test, in which the driver will floor it while moving and the car in gear, at a speed at or just above idle; it is going to take the better part of a second for the engine to get where the power is.
