718 GT4?
07-15-2019 | 12:39 PM
#8281
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They why did they use the name Sport 2 years later in the 991.2 GT cars?
The 991.2 did come out before the GT4 so was "designed" earlier.
07-15-2019 | 01:42 PM
#8283
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With the GT4, there are several corners where 2nd gear is optimal on the Nordschleife. If they were to gear the box for best Autocross performance and the typically slower road courses in the US (and to give us maximum fun on back roads), then I think there would be scant (if any) use for 2nd gear on that track (the one Porsche really cares about). Driving at the bottom of 3rd gear on the slower corners would make the Ring time slower (and they'd be using only 4 gears on the track compared to 5). And if they hit the limiter in 6th on Dottinger Hohe (or more likely exceeded 7,600 rpm on the Autobahn), that would obviously hurt too. And if there was a wider gap between 5th and 6th gears (or any others), that would come with a time penalty too.
07-15-2019 | 02:12 PM
#8285
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Yes, hopefully the PDK will have 7 performance gears (and not just 6 like the Clubsport or all the other 718 and Carrera models - I think in the 992 both 7th and 8th gears are very tall overdrives for noise, emissions, and consumption reduction).
07-15-2019 | 02:33 PM
#8286
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The way they achieved the 997.2 GT3 RS ratios actually did make the gap from 5th to 6th gear wider and more inefficient. They used a lower final drive (ring & pinion) and then modified 6th gear (taller) to retain Vmax. So they effectively lowered 5th gear (in addition to 1st through 4th) and kept 6th tall. This may be a totally fine trade-off (and probably one that I would prefer for most of my driving), but it certainly was trading away high speed acceleration in that bargain.
All gearing is a trade-off. One that Porsche has made countless times before. And every previous time they did they came to a very different conclusion vs the GT4.
When the 997.2 GT3 RS was carrying the flag against the GT-R at the Nurburgring they shortened the gears vs ratios that were already well shorter than the 981’s. In fact every 6 speed Porsche has featured a shorter 2nd. Even the 5 speed in the 964 3.6 Turbo used a noticeably shorter 2nd- you need to go all the way back to the 930’s 4 speed to find a taller 2nd gear (90 mph vs 84).
Did Porsche learn something new about how to gear a car in the last decade? Something that happens to be unique to the Cayman and does not apply to the 911 or GT3?
The acceleration chart I posted was recycled from the 981. If someone cares to revise for the 781 it will be fairly obvious that re-spacing the gears can result in virtually imperceptible loss on the higher end but a massive gain on the low end, one that would be felt not just at the autocross and on back roads but many tracks from Laguna Seca on down. In light of which it’s simply incredulous to think that Porsche chose an 84 mph 2nd for performance reasons.
07-15-2019 | 02:45 PM
#8287
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Cornering speeds at the Ring are higher, due to improvements in tires, the track, and the chassis developments. And most models have higher Vmax as well (comparing like models), compared to a decade ago. Not saying this is enough to cause much difference to the gearing - just facts for consideration...
07-15-2019 | 03:19 PM
#8288
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I still find it silly to gear a car for two environments that most cars will never experience and compromise the driving experience for the other 99% of the cars. If my typical speed limit around town in my area is approximately 45 mph and taking into account I speed (which I do), I would essentially never leave first or second gear to have any reasonable response from the engine. So now you're the tool riding around at 5k rpm
Top speed, IMO, is for bragging rights and serves no real purpose in the real world. Even if you do run it to vmax on the Bahn, how long can you comfortably sustain that?
07-15-2019 | 03:21 PM
#8289
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997.2 GT3 RS equivalent ratios would work great. No inefficient jumps or lowered top speed vs the GT4, and the shorter 2nd gear didnt hurt that car at on the track in the slightest. I also dont buy the idea that the tall gearing was required for emissions or cost. Both are like saying the 3.8 x51 or GT3 engines dont fit- possibly technically true if youre unwilling to do the slightest modifications, but not something Porsche engineers couldnt easily overcome if they felt like it.
The real answer for why they wont lower the gear ratios is both simple and one they cant admit- it would make the car too good. Drop 2nd gear by 10 mph and youd drop 0-60 by a few 10ths, harry GT3s at the autocross and make the car more enjoyable on back-roads. All of these would threaten or eclipse the nexts rungs up in Porsches cost/ performance ladder making those cars seem like significantly worse value. And while it is in Porsches interest to appeal to a hardcore audience on a relative budget its absolutely not in their interest to upset their apple cart. So much like the 944 turbo (the GT4s spiritual predecessor) expect it to be hobbled until either it gets more expensive or the cars above it in Porsches lineup get faster (see the 944 Turbo S and the release of the 964).
Porsche can reduce the GT4s gear ratios. They choose not to.
The real answer for why they wont lower the gear ratios is both simple and one they cant admit- it would make the car too good. Drop 2nd gear by 10 mph and youd drop 0-60 by a few 10ths, harry GT3s at the autocross and make the car more enjoyable on back-roads. All of these would threaten or eclipse the nexts rungs up in Porsches cost/ performance ladder making those cars seem like significantly worse value. And while it is in Porsches interest to appeal to a hardcore audience on a relative budget its absolutely not in their interest to upset their apple cart. So much like the 944 turbo (the GT4s spiritual predecessor) expect it to be hobbled until either it gets more expensive or the cars above it in Porsches lineup get faster (see the 944 Turbo S and the release of the 964).
Porsche can reduce the GT4s gear ratios. They choose not to.
07-15-2019 | 03:27 PM
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07-15-2019 | 03:30 PM
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Cornering speeds at the Ring are higher, due to improvements in tires, the track, and the chassis developments. And most models have higher Vmax as well (comparing like models), compared to a decade ago. Not saying this is enough to cause much difference to the gearing - just facts for consideration...
07-15-2019 | 03:36 PM
#8293
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From: WA
It's obvious that the same 6 speed gearbox was reused in the 718 GT4 to reduce development cost and to avoid stepping on the 911's toes, like always. The idea that the ratios were 'optimized for the Nürburgring' is ridiculous since the 718 GT4's ratios are exactly the same as a 987.2 Boxster S and every other 6 speed 981 and 718. They just keep reusing it without modification.
07-15-2019 | 03:44 PM
#8295
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It's obvious that the same 6 speed gearbox was reused in the 718 GT4 to reduce development cost and to avoid stepping on the 911's toes, like always. The idea that the ratios were 'optimized for the Nürburgring' is ridiculous since the 718 GT4's ratios are exactly the same as a 987.2 Boxster S and every other 6 speed 981 and 718. They just keep reusing it without modification.