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trip said:
310 could also be just another conservative number from Porsche. I wonder how many car magazines will actually try and hit top speed and how many will just rely on Porsche's claim.
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LoranTw said:
In combination with gear ratios and horsepower how does 200 miles per hour compute...is it possible with those pieces of information to arrive at terminal speed..or is it that simple?
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Crash said:Quote:
MKSGR said:Quote:
RC said:Quote:
MKSGR said:
There is no speed limiter in the 997TT. The gearing of the 997TT limits the top speed to ca. 310kph. Same as in case of the 996TTS: Top speed of 307kph was reached at maximum allowed revs. The shorter gearing supports acceleration performance but reduces top speed.
I asked you before: are you sure? The 996 Turbo S had a shorter 6th gear compared to the 996 Turbo.
All rumors indicate that the 997 Turbo is speed limited...because of the tires. I still didn't figure out the reason behind this but apparently it has to do with the CUP tires and not the street tires. It would be impossible to limit cars with Cup tires only, so they limited ALL versions. IF true (still no official confirmation), this would be ridiculous. I'll find an answer soon...hopefully.
Just take a look at the recent AMS test. The rev/hp/speed chart confirms that the car reaches ca. 310kph at max revs in the 6th gear. This is a pretty convincing argument, don't you think so
I am really worried that all this VTG technology and 480hp is not good for much: The 997TT *needs* a short gearing to show at least slightly improved acceleartion figures and to keep up with its competitors. No good news indeed
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Also, I've inserted the values into a calculator (http://www.kabamus.com/garage/gears.html). The speed at 6800 rpm should be approximately 200 mph, maybe a bit more, so RC's theory of an electronic cutoff seems very likely.
Values used:
Tire Width in (mm): 305
Aspect Ratio: 30
Rim Diameter in (inch): 19
Transmission Gear Ratio: 0,79 (6th gear)
Differential Ratio (final drive): 3,33 (rear)
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Crash said:Quote:
LoranTw said:
In combination with gear ratios and horsepower how does 200 miles per hour compute...is it possible with those pieces of information to arrive at terminal speed..or is it that simple?
Note that the Turbo has almost 480 horsepower still available at redline, so 200 mph is nothing, really. It's all in the gearing. The old Ruf yellowbird achieved over 340 km/h with 470 HP, by using a long enough gear..
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Tony007 said:Quote:
Crash said:Quote:
MKSGR said:Quote:
RC said:Quote:
MKSGR said:
There is no speed limiter in the 997TT. The gearing of the 997TT limits the top speed to ca. 310kph. Same as in case of the 996TTS: Top speed of 307kph was reached at maximum allowed revs. The shorter gearing supports acceleration performance but reduces top speed.
I asked you before: are you sure? The 996 Turbo S had a shorter 6th gear compared to the 996 Turbo.
All rumors indicate that the 997 Turbo is speed limited...because of the tires. I still didn't figure out the reason behind this but apparently it has to do with the CUP tires and not the street tires. It would be impossible to limit cars with Cup tires only, so they limited ALL versions. IF true (still no official confirmation), this would be ridiculous. I'll find an answer soon...hopefully.
Just take a look at the recent AMS test. The rev/hp/speed chart confirms that the car reaches ca. 310kph at max revs in the 6th gear. This is a pretty convincing argument, don't you think so
I am really worried that all this VTG technology and 480hp is not good for much: The 997TT *needs* a short gearing to show at least slightly improved acceleartion figures and to keep up with its competitors. No good news indeed
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Also, I've inserted the values into a calculator (http://www.kabamus.com/garage/gears.html). The speed at 6800 rpm should be approximately 200 mph, maybe a bit more, so RC's theory of an electronic cutoff seems very likely.
Values used:
Tire Width in (mm): 305
Aspect Ratio: 30
Rim Diameter in (inch): 19
Transmission Gear Ratio: 0,79 (6th gear)
Differential Ratio (final drive): 3,33 (rear)
Looking at my US brochure it clearly states the final drive ratio of the manual rear diff is 3.44. The front diff is 3.33.
Will this change your calculations?
Quote:
Crash said:Quote:
MKSGR said:Quote:
RC said:Quote:
MKSGR said:
There is no speed limiter in the 997TT. The gearing of the 997TT limits the top speed to ca. 310kph. Same as in case of the 996TTS: Top speed of 307kph was reached at maximum allowed revs. The shorter gearing supports acceleration performance but reduces top speed.
I asked you before: are you sure? The 996 Turbo S had a shorter 6th gear compared to the 996 Turbo.
All rumors indicate that the 997 Turbo is speed limited...because of the tires. I still didn't figure out the reason behind this but apparently it has to do with the CUP tires and not the street tires. It would be impossible to limit cars with Cup tires only, so they limited ALL versions. IF true (still no official confirmation), this would be ridiculous. I'll find an answer soon...hopefully.
Just take a look at the recent AMS test. The rev/hp/speed chart confirms that the car reaches ca. 310kph at max revs in the 6th gear. This is a pretty convincing argument, don't you think so
I am really worried that all this VTG technology and 480hp is not good for much: The 997TT *needs* a short gearing to show at least slightly improved acceleartion figures and to keep up with its competitors. No good news indeed
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Also, I've inserted the values into a calculator (http://www.kabamus.com/garage/gears.html). The speed at 6800 rpm should be approximately 200 mph, maybe a bit more, so RC's theory of an electronic cutoff seems very likely.
Values used:
Tire Width in (mm): 305
Aspect Ratio: 30
Rim Diameter in (inch): 19
Transmission Gear Ratio: 0,79 (6th gear)
Differential Ratio (final drive): 3,33 (rear)
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Crash said:
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
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MKSGR said:Quote:
Crash said:
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Hm, just checked again: which dotted line? There is only a solid line that ends at 310kph (at max revs)...
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svtrader1 said:Quote:
Crash said:Quote:
LoranTw said:
In combination with gear ratios and horsepower how does 200 miles per hour compute...is it possible with those pieces of information to arrive at terminal speed..or is it that simple?
Note that the Turbo has almost 480 horsepower still available at redline, so 200 mph is nothing, really. It's all in the gearing. The old Ruf yellowbird achieved over 340 km/h with 470 HP, by using a long enough gear..
"Yellow bird" had about 540hp.
Quote:
Crash said:Quote:
svtrader1 said:Quote:
Crash said:Quote:
LoranTw said:
In combination with gear ratios and horsepower how does 200 miles per hour compute...is it possible with those pieces of information to arrive at terminal speed..or is it that simple?
Note that the Turbo has almost 480 horsepower still available at redline, so 200 mph is nothing, really. It's all in the gearing. The old Ruf yellowbird achieved over 340 km/h with 470 HP, by using a long enough gear..
"Yellow bird" had about 540hp.
With boost cranked. The one tested in 1987 only had 469. Not that this applies to the bigger 997TT directly, but it shows that it doesn't take all that much horsepower.
Also, FINAL DRIVE
According to Auto Zeitung:
Rear: 3,33
Front: 3,44
That would make sense, since the front wheels are somewhat smaller.
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svtrader1 said:Quote:
Crash said:Quote:
svtrader1 said:Quote:
Crash said:Quote:
LoranTw said:
In combination with gear ratios and horsepower how does 200 miles per hour compute...is it possible with those pieces of information to arrive at terminal speed..or is it that simple?
Note that the Turbo has almost 480 horsepower still available at redline, so 200 mph is nothing, really. It's all in the gearing. The old Ruf yellowbird achieved over 340 km/h with 470 HP, by using a long enough gear..
"Yellow bird" had about 540hp.
With boost cranked. The one tested in 1987 only had 469. Not that this applies to the bigger 997TT directly, but it shows that it doesn't take all that much horsepower.
Also, FINAL DRIVE
According to Auto Zeitung:
Rear: 3,33
Front: 3,44
That would make sense, since the front wheels are somewhat smaller.
I have that issue of Road and Track that tested the "yellow bird" in '87. It was later dynoed to have about 540hp.
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Crash said:Quote:
MKSGR said:Quote:
Crash said:
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Hm, just checked again: which dotted line? There is only a solid line that ends at 310kph (at max revs)...
GETRIEBEDIAGRAMM:
The line that is labeled Nennleistung 480PS goes up to 6800 rpm, and then becomes dotted, up to 7200 rpm - 6th gear.
Quote:
MKSGR said:Quote:
Crash said:Quote:
MKSGR said:Quote:
Crash said:
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Hm, just checked again: which dotted line? There is only a solid line that ends at 310kph (at max revs)...
GETRIEBEDIAGRAMM:
The line that is labeled Nennleistung 480PS goes up to 6800 rpm, and then becomes dotted, up to 7200 rpm - 6th gear.
Not in my AMS issue... The solid line ends at 310kph, there is no dotted line (page 68)
Quote:
Crash said:Quote:
MKSGR said:Quote:
Crash said:Quote:
MKSGR said:Quote:
Crash said:
It doesn't actually say so. Also, what's the dotted line that goes beyond the solid line over 320 km/h? Seems to be the front differential?
Hm, just checked again: which dotted line? There is only a solid line that ends at 310kph (at max revs)...
GETRIEBEDIAGRAMM:
The line that is labeled Nennleistung 480PS goes up to 6800 rpm, and then becomes dotted, up to 7200 rpm - 6th gear.
Not in my AMS issue... The solid line ends at 310kph, there is no dotted line (page 68)
Whoops, I'm talking about Auto Zeitung !
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MKSGR said:
That would be good news Let's wait and see.
BTW: We did another high-speed comparison of a friends M6 vs my 996TTS last week.
This time the M6 had identical acceleration figures up to my car's to speed of 326kph (according to speedo, should be around real 310kph). Unfortunately, my friends M6 kept pulling... However, this M6 was also noticably quicker at higher speeds than the M6 we used for our last test 6 months ago - so it is fair to say that my friends delimited M6 has got one of the stronger engines