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Top Gear compares P85D with i8 on a race track...

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Yeah. There is basically no street legal situation in the U.S. the P85D would be 'trounced' by the i8. Ok the track, sure. It's not a track car. If the i8 is such a superior car why isn't BMW outselling the Model S?
 
Please point me to where Tesla claim the P85D is a track car?

So what? The i8 isn't being promoted as a "track car" either. Volkswagen doesn't promote the Golf Station Wagon as a "track car" - and that one was also faster than the Model S.
Top Gear doesn't bother if cars are claimed to be "track cars", they just take some fast cars and put them on a track.

It's really quite cute. The whole forum is full of posts "Model S racing x y, z" - all drag races. Strangely no one protests that this isn't what the Tesla is made for. Yet have someone dare to race the Tesla outside of its core discipline and people start to sulk.
 
So what? The i8 isn't being promoted as a "track car" either. Volkswagen doesn't promote the Golf Station Wagon as a "track car" - and that one was also faster than the Model S.
Top Gear doesn't bother if cars are claimed to be "track cars", they just take some fast cars and put them on a track.

It's really quite cute. The whole forum is full of posts "Model S racing x y, z" - all drag races. Strangely no one protests that this isn't what the Tesla is made for. Yet have someone dare to race the Tesla outside of its core discipline and people start to sulk.

Umm No. The Model S is made for straight line acceleration. That's what the EV power train excels at. If you point is basically any ICE can run almost non stop on a track and not get power limited due to heat then pat yourself on the back. You are correct. One car can't be all things to all people. The Model S is not a good track car. Can the Golf go 0-60 in under 3 seconds? No? Maybe it isn't the perfect car either.

Either was the i8 is a weak performer for how it looks and how much it costs. If it isn't a good track car either what exactly is the point of the car? It also runs out of max power once the battery pack is depleted leaving it with a weak ICE I thought. So it has a small battery pack, can't maintain max power and costs a lot. It is a very cool looking car. That's basically its main selling point.
 
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Having actually driven our Model S on a track at Refuel 2015, I have to reaffirm that.... it's not a great track car. And that's totally fine. It handles well for its size and accelerates quickly and does all this with you in a luxurious, silent cocoon, the main drawback being lack of sustained power. What I don't get are all these people running to Tesla's defense as if they're part of their legal team or something .. "umm...it was never actually STATED blablabla." No need to keep this stuff hush hush like we're some paranoid PR department - if somebody wants a track car by all means let them be informed, LET IT BE KNOWN that the Model S is not the car for them.

From everything I've read about the i8 it doesn't sound like a very good product. I fully intend to test drive one soon. It seems like an OK track car with tons of disadvantages in every day practicality and a huge price tag. It's also slower off the line compared to some versions of the Model S.

If you're looking for a good track car that isn't purely ICE maybe some future form of the VW GTE will do. <30k which is perhaps the most important part because if you plan on tracking it for any significant amount stuff is going to break, perhaps catastrophically.

Also worth thinking about - electric motors in performance vehicles that require sustained power at levels such as in the Model S are fairly new - I expect to see fairly fast improvements in this area in the coming years. Think about how long it took for humanity to have reliable high performance gas engines. We're already most of the way there this time!
 
I'd imagine Tesla could make the Model S track capable someday with better cooling. It's just not something they are focused on right now and that's ok. Agree with above. Not making excuses for the Model S. It just is obviously not a good track car. If that's an issue then it's not the car for that person.
 
I'd imagine Tesla could make the Model S track capable someday with better cooling. It's just not something they are focused on right now
I wish there was a way for us to motivate this within Tesla as owners. Frankly, I don't care if it's a Tesla internal effort or a partnership with a 3rd party -- but with Tesla's blessing and assistance as needed.

I get the impression, though, from multiple sources in and near Tesla that it's, shall we say, "significantly frowned upon" to even mention engaging the track enthusiast crowd and evaluating improvements in that regard. I find this shortsighted and disappointing. :(
 
I wish there was a way for us to motivate this within Tesla as owners. Frankly, I don't care if it's a Tesla internal effort or a partnership with a 3rd party -- but with Tesla's blessing and assistance as needed.

I get the impression, though, from multiple sources in and near Tesla that it's, shall we say, "significantly frowned upon" to even mention engaging the track enthusiast crowd and evaluating improvements in that regard. I find this shortsighted and disappointing. :(


I disagree....Tesla, Elon, and friends repeatedly allude to "Supercar acceleration." Performance is clearly part of the DNA and spirit of the company. Hell, look at their first car, the Roadster. I think it's just an incredible balancing act between the technology that's available today, practicality, and potential future viability... time heals all things.
 
I disagree....Tesla, Elon, and friends repeatedly allude to "Supercar acceleration." Performance is clearly part of the DNA and spirit of the company. ...
I'm not sure it is. Well, more specifically I'm not sure "performance after the first 5 minutes" is on their radar for at least the next decade.

Yes, I'm talking about the "sustained performance" problem.

As an example, would Intel make much money selling a CPU that can run 4x as fast in the first 5 minutes than it can for the rest of the hour? Probably not. And they definitely wouldn't call it a "performance" CPU.


As for the general assertion that the Model S isn't a track car... I see sedans from other brands (primarily Audi and BMW, but others too) at the track quite often. I thought "quickest sedan" and "performance sedan" was a key part of the billing for Model S. Why shouldn't it be capable of being a track car? Besides the acceleration limiter (heat?), what are the near-term insurmountable shortcomings? And why shouldn't Tesla care about overcoming them? Like it or not, the track performance of a vehicle affects the brand and the tech (EV vs. ICE) as a whole at a social level. Winning hearts and minds requires a multi-front effort.
 
I wonder if the new Inconel contactor / smart fuse would help in the sustained performance of Model S. I assume lots of track driving would be at, or near, max power draw, and if the fuse and/or contactor was a limiting factor in discharge it might help.
 
I wonder if the new Inconel contactor / smart fuse would help in the sustained performance of Model S. I assume lots of track driving would be at, or near, max power draw, and if the fuse and/or contactor was a limiting factor in discharge it might help.

While there's a serious dearth of information available to the public about exactly why the car is pulling power, the best explanations I've heard suggest it is driving motor rotor heating - or possibly even predicted drive motor rotor heating - that is causing the response.

It's not easy to cool the rotor of an electric motor. Tesla apparently uses a hollow shaft and pumps coolant through it. From some european documents, it's been suggested that the continuous rating on the P85 might only be ~70 kW (though it'll let you have 300+ kW for acceleration.)

Siemens apparently came up with some innovative solutions here for their prototype aircraft electric motor, which might be suitable for future Tesla efforts. They claim to be able to sustain 260 kW from a 50 kg (110 pound) electric motor at 2500 rpm.

That kind of continuous rating could make a trackable Tesla practical, if approach they used is otherwise suitable - and the lower RPM would mean less gearing needed.
Walter
 
I wonder if the new Inconel contactor / smart fuse would help in the sustained performance of Model S. I assume lots of track driving would be at, or near, max power draw, and if the fuse and/or contactor was a limiting factor in discharge it might help.

I wonder if then it might be worthwhile, for not only sustained performance reasons but longevity reasons as well, to get these upgrades on a non P85d model S. While it might not come into play in 0-60 times for the non-P models, perhaps it would offer sustained levels of power at the respective model's respective performance level.


While there's a serious dearth of information available to the public about exactly why the car is pulling power, the best explanations I've heard suggest it is driving motor rotor heating - or possibly even predicted drive motor rotor heating - that is causing the response.

It's not easy to cool the rotor of an electric motor. Tesla apparently uses a hollow shaft and pumps coolant through it. From some european documents, it's been suggested that the continuous rating on the P85 might only be ~70 kW (though it'll let you have 300+ kW for acceleration.)

Siemens apparently came up with some innovative solutions here for their prototype aircraft electric motor, which might be suitable for future Tesla efforts. They claim to be able to sustain 260 kW from a 50 kg (110 pound) electric motor at 2500 rpm.

That kind of continuous rating could make a trackable Tesla practical, if approach they used is otherwise suitable - and the lower RPM would mean less gearing needed.
Walter
Would this offer the same kind of torque? If not, a dual motor setup could compensate to maintain a similar torque curve.
 
I wonder if then it might be worthwhile, for not only sustained performance reasons but longevity reasons as well, to get these upgrades on a non P85d model S. While it might not come into play in 0-60 times for the non-P models, perhaps it would offer sustained levels of power at the respective model's respective performance level.



Would this offer the same kind of torque? If not, a dual motor setup could compensate to maintain a similar torque curve.

I don't know much about the Siemens prototype for certain, but most AC motors behave similarly and would have the instant low rpm torque we all love and I see no reason to expect this one to be an exception.
 
I'm not sure it is. Well, more specifically I'm not sure "performance after the first 5 minutes" is on their radar for at least the next decade.

Yes, I'm talking about the "sustained performance" problem.

As an example, would Intel make much money selling a CPU that can run 4x as fast in the first 5 minutes than it can for the rest of the hour? Probably not. And they definitely wouldn't call it a "performance" CPU.

(snip)

Wrong analogy…

A (intel) processor has a stated "base" frequency, and a "turbo" (or up-to) frequency. When you buy OEM, especially in cheap laptops, the cooling system is often undersized so in long, sustained max power runs the processor will automatically dial the frequency back (way back if needed) to keep its temperature in check. Does it rings a bell ? ;-)

But we don't notice it as most computer users won't use a CPU at it's maximum. And even when you run something intensive, it will be interrupted by many small pauses waiting for disk access or anything such that the processor will have to opportunity to cool itself. Which we don't really have when running a car on the track. I've never raced, but I would guess that the only time when little power is needed is during turns. Otherwise the car is at max throttle (or max regen) right ? So I guess to apply the 'micro pauses' logic from computers to cars we would need a track with lots of turns or — gasp — an ICE to take care of the long stretches of high power (that's where ICE's are good.)

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I am also curious about how we can improve the sustained power of the electric motors. Electric motors have been used in the transport (think trains) and the industry in general for a long time, so I would guess that we are capable of designing reliable, high sustained power electric motors. But at what cost (size, weight and $) ? I'm looking forward learning more about that Siemens motor.