From 6 Speed Online -
Did I miss what was new?
Interesting, apparently Tesla blew more than just the doors off :)
They act as though Tesla hasn't done or doesn't do all of these things.
Now we know why its slower, has less range and costs more
2-speed transmission...... oh porsche.....
Does that two speed transmission have a real advantage at very high speeds? Porsche isn't the first EV to have one, the RImac also uses a two speed transmission. The Rimac is a hypercar, it's built to go 220 MPH, I don't think anyone is going to drive a Rimac to Costco. The Porsche is built for the Autobahn, it's perfectly legal to drive at 200KPH or more on the Autobahn, everywhere else in the world you'll go to prison for driving at those speeds. At any reasonable speed a two speed transmission is an unnecessary piece of complexity, it provides no benefit and it's something that can go wrong, it's probably also a little less efficient at US highway speeds. But is it more efficient at 150MPH then a single gear? I'm assuming that it must be or Porsche wouldn't have put it in, but then again they might have done it for no other reason then they could.
@bjrosen - I expect Porsche had to use a transmission because the motor they choose has poor high-end torque. Torque does suffer a bit at high RPMs, but the motor design has a huge effect on how much torque is lost. Tesla seems to have figured out how to maintain suitable torque at high RPMs, where it looks like Porsche couldn't, and was forced to use a transmission to make up for it. Of course, the transmission creates its own inefficiencies, which may explain the poor overall efficiency and performance of the Taycan.
A quick simple explanation from Formula E.
Looking at the Taycan rear drive unit - it's huge. Looks to be twice the size and weight of the Tesla rear-drive unit, yet appears less powerful.
Electric motor efficiency goes down the higher the RPMs. The only time this would matter, is if you're actually driving like 200+ mph. In this car, you would barely be able to sustain those speeds. Not worth it. Tesla beat Porsche track time with 1 speed transmission. Its not necessary.
Plus the Roadster tried a 2 speed transmission and they were destroyed by the torque apparently.
I completely understand the need for a transmission for either an ice or electric motor to stay in the most efficient torque/HP zone. However, the top speed of the Taycan and the Model 3 for example are the same, so why does Porsche need more than one speed? does the Taycan get to top speed faster than a Model 3 performance?
Now that half the car is torn down, maybe it can sell at the price of a P100D.
They better put it back together quickly if they hope to beat Tesla's Nurburgring time. I guess it's pointless either way.
They’re competing with themselves at this point. They are not in the same class as Tesla with that kind of timing disparity. Never wake the bear.
Not being a mechanical engineer, I really have no idea, but doesn't the Model 3 dual motor use the front and rear motors differently at different speeds, perhaps negating the need for a two speed transmission?
I thought that, on the Model 3, the rear is induction, but the front is permanent magnet??
RedPillSucks, I recall reading something along those lines. Might have had more to do with higher speed (interstate speeds) efficiency, but that efficiency advantage might well contribute to the performance end of things as well.
Two speed transmission is intended only to reduce the motor efficiency losses at very high RPMs. In this case, we are easily talking well over 100mph, which no average person will ever be driving at. So the two speed transmission concept to reduce efficiency losses will be used exclusively for someone who does some type of racing. And even then, to save a few percent losses by adding a second gear which cuts down on torque doesnt actually make any sense.
The two speed transmission is great for racing. It reduces wear and tear on the engine and increases efficiency by reducing engine overheating. I believe this is what allows Porsche to handle endurance races better....
Does anyone know if the front and rear motors are the same technology? They could balance the performance slow/fast with different motors also...
"The two speed transmission is great for racing. It reduces wear and tear on the engine and increases efficiency by reducing engine overheating."
It could potentially save some life on the bearings. On the otherhand, Tesla has achieved 1 million miles on their electric motors and it was still working afterwards. So i dont really know if reducing wear and tear on the motor is an accurate argument to make. I dont think Porsche is doing the best they can here. 2 speed transmission in an EV is unnecessary.
You're forgetting the biggest issue with a Porsche transmission: Porsche's transmission crew would be out of work if the Taycan didn't have a transmission.
Also, conventional wisdom calls for a transmission. Legacy folks can't get past this.
Why do you think hybrids are popular while pure BEVs aren't with the major car companies?
Why the Model S almost made Tesla bankrupt because of Transmission problems in 2008 if..... it doesn't have transmission?
hybrids also have one speed transmissions.
1) When the transmission has to change gears, the car has zero propulsion power. For example, going from 1 to 2, requires the motor to be disengaged, the motor spun down wasting energy and time, before going to the higher gear. The more gear shifts in a race, the poorer the performance over a vehicle without a transmission.
2) Perhaps a transmission reduces wear on an ICE engine, but zero on a well-designed EV. In addition, now you have a transmission that wears, needs to be cooled, and perhaps replaced after every race or two. The clutch plates take a beating in a race.
Taycan engineers likely had to use a transmission, because the motor design they choose is low-torque or limited RPMs. It's their first EV, so not too much of a surprise that they couldn't duplicate what Tesla has done.
It was the first Roadster that had a 2-speed transmission, not the Model S. They only made one that way. It was serial 001, musk's own car. Serial 002 and higher all had the upgraded digital Power Electronics Module and the single-reduction-gear instead of a transmission.
Some would argue that most hybrids have a variable-speed transmission. They are necessary to keep the finicky ICE working at the right RPM. Some Honda hybrids actually have a conventional 5-speed manual transmission.
@TT is probably correct. Like most ICE engineers who are used to sizing an ICE for a car's performance, they under-sized the electric motor, therefore, they had to choose between poor low-end acceleration and top speed.
I wonder what a CVT would be like...
A CVT would be shredded at these torque levels.
That said the Prius CVT is a tank, I put 400k on one and the kid is now commuting to college with it. The CVT in the Honda Insight sucks. It has turned my wife off to hybrid's and Ev's.
Not all CVT's are the same, and it just takes one poor implementation of a technology to turn a person off to it forever.
I really hope the Taycan, I-Pace, and E-tron don't leave similar sour tastes.
^^^ Not a well-designed on for this application.
Apparently this Taycan prototype had been working out at the Ring since May--took 4 months to lay down an unofficial made-up record. Tesla did it in what, 4 days?
The pace of innovation that Tesla wields repeatedly makes traditional conventional legacy ICE automobile manufacturers look silly.
@ ReD eXiLe ms us
I don’t think that’s quite fair. Internal combustion is a stable technology near its peak. Innovation is more achievable in an immature field.
Going fast is all well and good, but a revolution in battery energy density is the event horizon I’m looking forward to.
So, if the Taycan had been working the ring since May, maybe sending the Plaid S was not a knee jerk reaction, but planned once the final numbers where in... I know, conspiracy theories.
MAB1980: Nah. It's perfectly 'fair'. EV NaySayers claimed for YEARS that the inherent ADVANTAGE of ICE was that it was a 'MATURE TECHNOLOGY'.
They literally said, "Until batteries can MATCH the energy density of gasoline, battery electric vehicles DON'T stand a chance." But... they were WRONG.
They can't have it both ways. If their 'maturity' is an advantage, then that means they could have tapped into MORE POWER and BETTER EFFICIENCY ages ago, but chose not to, deciding to eek out incremental improvements and planned obsolescence ad infinitum for the sake of the all mighty dollar.
If their maturity is a DISADVANTAGE instead, then they should cut bait NOW and switch horses mid race. Which will it be? No one wants to take the responsibility of being the ONE who made the decision to go fully electric. Th ef ir 'LEGACY' might be tarnizhed as a result. And what will happen to your Legacy if you choose NOT to change, lose tremendous amounts of market share and go bankrupt... AGAIN...?
Each traditional conventional legacy ICE automobile manufacturer has gradually learned what I have been telling them for five years is true. HYBRIDS are NOT 'a path forward' or 'a bridge to... The FUTURE!' Instead, they are a roadblock, a stopgap, to delay the onset of 'The FUTURE!' everyone knows MUST happen, so that it doesn't happen 'too soon'. Read: Before executives can retire without taking on the issue of change with a huge severance package and Golden Parachute before moving on.
The first days of a new technology may seem lacking compared to the last days of an old technology. Ledger pads and pencil worked GREAT for accounting for CENTURIES. Then came calculating machines, and electronic calculators, and for a time the old pencil & psper methods were employed side by side with machines far more complicated than a bead abacus. Then computer programs like Lotus 1-2-3. Then came EXCEL. That transition may have been hard, but it happened anyway. The Old Guarde couldn't prevent it, no matter their personal preference. The invention of and improvement of and the innovation for what became spreadsheets was not anything that anyone with a banker's visor and desk lamp could have seen coming in circa 1938. By 1988 it was all over. As soon as information became known as 'data' way back in 1958 nomenclature it was over. The sheer speed of data acquisition and dissemination meant that the 'old ways' were gone forever. Replaced.
Expect a similar, but quicker, progression as ICE dies its last and final breath. Not from a lack of people wanting them. So much as an abundance of people wanting electric drive instead. Just as people don't WANT POS ICE vehicles, like the Chevette or YUGO, people won't want POS EVs either. 2% market penetration will become 8%, then expand beyond 32%, then 98% EVs will rule new car sales and ANALysts all over will be aghast, wondering, "How'd this happen?" exclaiming, "Aye dinna see it coming..." This WILL h as ppen, SOON. Just watch.
Batteries have reached gasoline performance, because an internal combustion engine is some 30% efficient. Next please.
For those just postulating without direct knowledge:
Tesla is already quicker to 60 AND has a better top speed.
For those who ignore facts.
the table just after the graph says it all. Thats why i say its unnecessary. All the 2-speed transmission does is increase torque for the first 47mph, and then the graph slope dips below single speed. I've already stated that a 2-speed transmission is unnecessary in an EV, and the table proves it. All the extra parts and more areas of possible failure for what? You dont need 2-speed transmission to get faster 0-60 speeds, it just add unnecessary costs and areas for potential failure and maintenance.
I haven't studied the torque curves, but you're saying that the second gear was added to increase low end torque and not as a high speed gear to maintain power at triple digits? That's pretty shocking seeing as low end torque has never been a concern as traction is the limiting factor on a Tesla.
Correct. The second gear is not there to increase maximum speed. If you open the link @howard provided, the torque curve is compared with a single speed. And the 2-speed is only higher up to 47mph, and then it dips under the 1-speed until it overtakes it again at 60mph, and maintains that lead by an extremely small margin.
Electric motors are already extremely efficient, they do not need multi-geared transmissions because for an electric motor, power in = power out with a few % losses. Gas engines are some 30% efficient so they require being geared to get the torque at higher speeds.
If you add gears to an electric motor shaft, you're basically doing a ratio conversion where you reduce motor speed but add an equivalent amount of extra energy to compensate.
Also, its not that im saying it was added to do that, its quite literally all that it is doing.
@ ReD eXiLe ms us
“Nah. It's perfectly 'fair'. EV NaySayers claimed for YEARS that the inherent ADVANTAGE of ICE was that it was a 'MATURE TECHNOLOGY'.
They literally said, "Until batteries can MATCH the energy density of gasoline, battery electric vehicles DON'T stand a chance." But... they were WRONG.”
I think you’re conflating two things, or I misunderstood the post I responded to. My point is that it’s much harder to improve once a product is mature. That has nothing to do with a performance comparison. It’s simply recognizing that there are more gains to be made with batteries than with internal combustion. Improving energy density is the critical path towards electric flight (outside short range with few passengers).
Elon originally thought the 2 speed approach was better but could not get past reliability issues so abandoned the effort to concentrate on making the best he could with a single speed. Porsche has demonstrated that they also feel Elon’s Initial 2 speed approach is better and are confident that the reliability issue Tesla could not solve has been overcome.
You fail to address that Tesla does better with one gear than Porsche with two. The jury is absolutely still out on the long term durability of a multi gear EV transmission. Perhaps with it’s less efficacious motor, it won’t be as stressed as Tesla’s was.
Bighorn, wonder why Elon thought it better but could not make it reliable? You really know why? Perhaps same rationale Porsche is using. With your thinking how much better could a Tesla have been had it been able to implement 2 speed.
howard, again your talking point is inside out. Why doesn't the Porsche have better acceleration and better top speed with a 2 speed? You really are just out to play with words to criticize Tesla.
I think seeing the difficulty with the 2 speed transmission, they engineered a better motor. I don’t think they sat idly by and accepted defeat. Clearly they’ve succeeded given their unprecedented performance benchmarks.
No the constant non Tesla bashing gets really old even when pointed out that Elon’s best thought approach was initially 2 speed. Someone else decides to use 2 speed and you still trash them without really knowing the rationale of why a very large successful engineering group decided it was also a better approach. Not arguing for the sake of arguing just pointing out the total hypocrisy. Just gets very old!!
I think I pointed out that Porsche was about 10 years behind Tesla including trying a 2 speed transmission. Just an observation. Not bashing. But they do a lot of shit-talking, so when their performance doesn’t match their boasts, they should pull up their panties and take it like a big girl, as should you.