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The Porsche Taycan's Two-Speed Gearbox

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Re: The Porsche Taycan's Two-Speed Gearbox

#41

Post by minhazm »

milkytron wrote: post #7
gleglegle wrote: post #5

It's a little surprising that even with a two-speed Gearbox the Taycan has neither better range nor low range 0-60 acceleration than the Tesla P100D (which has the same size battery). Obviously spec comparisons aren't the whole story and the handling and high-range acceleration may be better on the Taycan. Looking forward to seeing more comparisons and already glad to see more EV models in this category. Edited incor…

According to the article: > It’s programmed to shift between its two speeds at 43 mph, though the computer can be programmed to make the change at different points based on the route, topography, or the distance the driver hopes to cover before plugging in. I wonder if that shift point has anything to do with the slower acceleration. I'd imagine it would make a small difference. As for the top speed, I believe Tesla…

Model S top speed is 163 mph.

Re: The Porsche Taycan's Two-Speed Gearbox

#42

Post by adrr »

rconti wrote: post #35
adrr wrote: post #29

Earlier quoted context omitted.

Nurburgring Ring times. P100D has terrible thermal management and goes into limp mode before completing the course. If people really cared about 0 to 60 times, we see a lot more Dodge Demons on the road instead of 911s and Corvettes. If Porsche can get price point for a regular Taycan below $100k, i'll gladly trade in my Porsche and Tesla for one because it does everything i want. I can drive canyon roads and never h…

Sure, and it's an ancient car, by EV standards. I'd hope that a Porsche that nobody has taken delivery of yet and costs way more is better. Last time I was at the track (in my BMW M car, mind you) we had a couple of Model 3 Performance cars, and a couple of Model S. I could pass the Model S with ease. I couldn't get close to the Model 3 Performance.

Model 3 performance needs ceramic brakes for the ring. Car is too heavy for the Brembos and it is at the limit for brake size.

Re: The Porsche Taycan's Two-Speed Gearbox

#43

Post by Cshelton »

rconti wrote: post #35
adrr wrote: post #29

Earlier quoted context omitted.

Nurburgring Ring times. P100D has terrible thermal management and goes into limp mode before completing the course. If people really cared about 0 to 60 times, we see a lot more Dodge Demons on the road instead of 911s and Corvettes. If Porsche can get price point for a regular Taycan below $100k, i'll gladly trade in my Porsche and Tesla for one because it does everything i want. I can drive canyon roads and never h…

Sure, and it's an ancient car, by EV standards. I'd hope that a Porsche that nobody has taken delivery of yet and costs way more is better. Last time I was at the track (in my BMW M car, mind you) we had a couple of Model 3 Performance cars, and a couple of Model S. I could pass the Model S with ease. I couldn't get close to the Model 3 Performance.

Which seems pretty reasonable...large family sedan vs a sports sedan.

Besides, when the new Tesla roadster rolls out in 2020/2021, it is game over for everyone else anyway. At a price point of ~$200k, it'll kind of make the Porsche Taycan a joke. Unless you are a Porsche only individual. Which, to their credit, is a fairly sizable market.

Re: The Porsche Taycan's Two-Speed Gearbox

#44

Post by elihu »

jameskilton wrote: post #9
elihu wrote: post #6

Seems logical. I think most manufacturers have just decided that they'd rather use an over-sized motor than deal with a transmission, but if you're willing to tolerate a more complicated drive-train you get more usable power with less weight. Using a transmission might get weird if you have multiple motors, though. For instance, it would be odd to have the front wheels in one gear and the rear wheels in a different g…

From what I've read, the AWD versions of the Model 3 (possibly others) actually do this (different ratios in the front and back). As the article says, Tesla had a hard time building a transmission that wouldn't tear itself apart under the torque of the electric motors. So, they put the front and back motors at different ratios. The back motor is used at lower speeds, and the front motor kicks in at higher speeds.

That makes sense for fixed-gear setups; I guess they just have to make sure that the lower-geared motor can spin at high enough RPM that it's not limiting the overall maximum speed. (Or perhaps they can use a freewheel mechanism, but that defeats using that motor for electronic braking.)

Having multiple motors each with their own switchable-gear transmission on the other hand might get hard to justify in terms of complexity.

Re: The Porsche Taycan's Two-Speed Gearbox

#45

Post by newnewpdro »

dragontamer wrote: post #40
gleglegle wrote: post #5

It's a little surprising that even with a two-speed Gearbox the Taycan has neither better range nor low range 0-60 acceleration than the Tesla P100D (which has the same size battery). Obviously spec comparisons aren't the whole story and the handling and high-range acceleration may be better on the Taycan. Looking forward to seeing more comparisons and already glad to see more EV models in this category. Edited incor…

> It's a little surprising that even with a two-speed Gearbox the Taycan has neither better range nor low range 0-60 acceleration than the Tesla P100D (which has the same size battery). 0-60 times probably don't matter on the track. Its probably more important to optimize the 60 to 120mph time, which is where the torque of a (single gear) electric motor begins to taper off. I bet that Taycan has superior 60-to-120mph…

> The only reason to push 0-60 times is for drag-racing really.

Wat? Most people care about accelerating from a standstill to the average legal speed limits.

0-60 captures that perfectly. It's incredibly relevant to the general public's driving patterns.

Re: The Porsche Taycan's Two-Speed Gearbox

#46

Post by rhinoceraptor »

mywittyname wrote: post #2

I'm surprised ZF/Porsche didn't turn this into an eCVT, as an eCVT (a la Prius) has probably the same complexity, but with the added benefit of having more ratios. I suspect it would also reduce shock loads on the transmission as a result of shifting. I wish the article would have gone into this, because I suspect Porsche said no more for marketing reasons rather than technical ones, as CVTs are universally hated in…

It seems like the advantage of a CVT only really apply to internal combustion engines since they can only really go from about 500 to 8,000 rpm, and in that range they only have peak power or peak efficiency in small ranges. EV motors can go from 0 to 18,000 rpm.

Re: The Porsche Taycan's Two-Speed Gearbox

#47

Post by Ididntdothis »

newnewpdro wrote: post #45
dragontamer wrote: post #40

Earlier quoted context omitted.

> It's a little surprising that even with a two-speed Gearbox the Taycan has neither better range nor low range 0-60 acceleration than the Tesla P100D (which has the same size battery). 0-60 times probably don't matter on the track. Its probably more important to optimize the 60 to 120mph time, which is where the torque of a (single gear) electric motor begins to taper off. I bet that Taycan has superior 60-to-120mph…

> The only reason to push 0-60 times is for drag-racing really. Wat? Most people care about accelerating from a standstill to the average legal speed limits. 0-60 captures that perfectly. It's incredibly relevant to the general public's driving patterns.

People rarely do a full power 0-60 with a car that can do it under 5 seconds. More likely they go from 30-60 or similar.

Re: The Porsche Taycan's Two-Speed Gearbox

#48

Post by 19870213 »

mrtksn wrote: post #21
gleglegle wrote: post #5

It's a little surprising that even with a two-speed Gearbox the Taycan has neither better range nor low range 0-60 acceleration than the Tesla P100D (which has the same size battery). Obviously spec comparisons aren't the whole story and the handling and high-range acceleration may be better on the Taycan. Looking forward to seeing more comparisons and already glad to see more EV models in this category. Edited incor…

I believe they just didn’t give the option to wreck your car by overclocking. Their selling point is repeatability, so overloading the systems is not part of the Taycan experience. Probably it’s possible to push the car to higher performance and risk performance degradation later on as with Tesla. Would be fun when people start playing around with these cars’ systems.

Porche appears to be claiming that one of the features of the Taycan is repeated launch control 0-60s without overheating or other problems that Telsa is warning people about when you use ludicrous mode: https://www.youtube.com/watch?v=TP9kokeyxGU

Re: The Porsche Taycan's Two-Speed Gearbox

#49

Post by johnvanommen »

AgloeDreams wrote: post #8

As I understand it, this gearbox type is key on Porche's intent to make it able to maintain performance over use rather than overheat, notably it improves acceleration and efficiency at high speed. I would expect the Taycan to use less energy to maintain 150mph.

Ah, that makes sense. So that it can cruise at high speeds efficiently.

Re: The Porsche Taycan's Two-Speed Gearbox

#50

Post by newnewpdro »

Ididntdothis wrote: post #47
newnewpdro wrote: post #45

Earlier quoted context omitted.

> The only reason to push 0-60 times is for drag-racing really. Wat? Most people care about accelerating from a standstill to the average legal speed limits. 0-60 captures that perfectly. It's incredibly relevant to the general public's driving patterns.

People rarely do a full power 0-60 with a car that can do it under 5 seconds. More likely they go from 30-60 or similar.

When a car does it silently without being overtly antisocial they do it far more often.
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