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Tesla Roadster

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46 pointsrobin_reala80 comments

620 mile range seems like a lot of battery weight for a performance car. Is that weight of batteries necessary to supply enough current and to reduce heat load on individual cells? Or would there be a smaller battery pack that would be even more performant due to reduced weight?

Yes, a larger battery pack can provide more power. You can see this at work in Tesla’s lineup already: the longer range variants also have better acceleration.

This range is not really surprising. Musk has previously stated that the performance limitation on the Model S has always been the battery. So the bigger the battery, the more juice you can pull for crazy launches. The 620 mile range is just a side-effect of putting in a bigger battery so it can hit the acceleration and top-speed numbers needed to put it in the super-car big-leagues.

Theoretically, you could get more performance out of a smaller pack, the VW ID. R used just 43kWH to set the electric record at the Nürburgring Nordschleife. However, that's a lightweight race car. Tesla seemed to want to make this a really livable car with lots of superlative records so by using super light construction paired with a massive battery they can build a car with incredible range (This range would be a production car record.) but that same pack can handle incredible draw. I imagine this will be like a model S on crack: It won't handle fantastic but will have hilarious power.

Also, they claimed that it was using twin Model S packs in their design but were planning to move to a Model 3 evolution based pack. (The Model 3's pack is much more energy dense due to larger, better, specialized cells.)

There are tradeoffs around capacity, power, and longevity. I suspect Volkswagen doesn’t care if the battery in their prototype racer is trashed after a year, so they can push it hard.

620 Miles range?! that's huge! for an all electric car, and beats even a lot of gas-powered cars

You only get 620 miles if you drive it like a Yugo. ;)

Otherwise, if you do lots of hard starts and stops, you'll probably get about 400ish.

Is that really true? Electric cars should theoretically be able to handle rapid acceleration more efficiently than ICE vehicles, and regenerative breaking makes deceleration less wasteful as well. How much energy would really be wasted by pushing the vehicle to its limits?

Those efficiency curves are nonlinear - anything involving what is wanted and what is not wanted in thermodynamics generally is.

So they unveiled it 2017, and now they are selling it? So now you can reserve. Hmm, maybe I missed it but when do you then actually get one? Is it the same thing like their other cars (i.e. when it is done)?

I am a bit confused about what is novel about this. It is not the unveiling, so it must be the reservation possibility but I might be wrong.

I just watched the video from the 2017 unveil and it says it will be available in 2020.

If that top speed ("Over 250 mph") is accurate wouldn't it put it in contention for "Production car speed record" per:

https://en.wikipedia.org/wiki/Production_car_speed_record

Additionally I hope nobody ever tries to "red line" it on a public road for their own and everyone else's safety. 4.2 sec 0-100 and a 250+ mph max is a very temping but potentially deadly combination.

Does anyone who owns a Tesla know if you can configure it to reduce the acceleration or artificially limit the top speed (e.g. "teenager mode" in other cars)?

Yes, you can via the app

It's probably not the first 6 figure supercar with dangerous specs.

Many of the cars on that list are 7 figure (or are in 2019 dollars). So we're likely going to see more of these types of cars on the road just given to its relatively lower price.

The Challenger Hellcat is ~$60k and similarly dangerous (~800hp, 0-60 mph in 3.4 seconds. Top speed - 203 mph. )...so I agree.

The Hellcat is dangerous, but I wouldn't say it's as dangerous as a Model S or Model 3 Performance, all that power can't hook so the Traction control lights are just flashing from a stop.

Meanwhile a Model S P100D is a whole second faster to 60 with this incredible 20mph 'JUMP' with zero lag, I got a test ride in one and felt as if something like a slip on the throttle off the brake would find you 20 feet inside a storefront, which there's a few examples of online lol.

https://electrek.co/2016/09/25/tesla-model-s-crashes-into-gy...

I'd argue the rear wheel drive makes it more dangerous. Lower velocity, but way more unpredictable.

Just look at all the videos of idiots spinning out and ramming spectators while leaving Cars and Coffee. You’d never be able to achieve that sort of loss of control in a Tesla.

You really have to work to be stupid with it though, the built in stability control has to be manually disabled and you have to be using the red key as well. Otherwise the Car's computer shuts it down.

Usually there are different driving modes. IIRC, in the Tesla sedans, "Chill" mode ups the 0-60 acceleration time to around 8 seconds.

There are a few ways in my Model 3:

- Valet mode - Set a max speed with a pin - Comfort vs. Sport which changes the driving dynamics drastically

At what performance point does a vehicle require specially designed tires? I assume you can't just put a set of Michelin Pilot Super Sports on this.

The Bugatti Veyron tires cost over $30k and last 2500 miles.

More interesting I think is lining up to beat the production figures too. Tesla are planning to make a lot more than 25.

Taking any car up to 250mph requires special tires and can only be achieved at a handful of test tracks. Most airport runways don't have enough room to do it.

> Does anyone who owns a Tesla know if you can configure it to reduce the acceleration or artificially limit the top speed (e.g. "teenager mode" in other cars)?

Yes it has both options however they're profile settings that can be changed by the operator. There's not parental profile or anything like that.

There's a valet mode which just nerfs the car all around but that's independent from the speedlimit and acceleration characteristics settings.

> Does anyone who owns a Tesla know if you can configure it to reduce the acceleration or artificially limit the top speed (e.g. "teenager mode" in other cars)?

In my Model 3, dual motor, I can do both: Limit acceleration and limit the top speed.

There are plenty of cars that are capable of taking out school busses full of nuns and orphans. The ‘16 Corvette driven by my 72 year old mother is a car I personally am incapable of fully thrashing on a public road without eventually slamming into something. And that only cost $50K.

The Roadster, should you be the kind of dumbass that can barely keep your ‘94 Camaro between the lines, will merely (please pardon the pun) accelerate the process.

November 16, 2017

The Lotus Evija looks better than this. But hey, that is a 1.5mil car.

The "250mph+" claim looks dubious given the shape/aero of this car - though I don't claim to be an expert and I suppose this might not be the finished shape of the car either.

Seems pretty aerodynamic to me. Can you point to a better shape?

Any other supercar; the parent posted one example.

The Lotus does not appear more aerodynamic than the Roadster. It has more "aggressive" features, but these do not improve aerodynamics and probably makes aerodynamics worse. The old Tesla roadster had a 0.31 drag coefficient (by the end of its run with Tesla's aero mods), Model S has 0.24, Model 3 has 0.23. I suspect the 2020 Roadster has better than the old Roadster, so somewhere between 0.30 and 0.20.

The large intakes of non-electric supercars also kills the drag coefficient.

The supercar Bugatti Veyron has a drag coefficient of 0.38.

So again, can you point to a more aerodynamic supercar? I'm not talking about subjective cosmetics (frankly, I find the cartoonishly "aggressive" features on lots of supercars a little childish), but objective aerodynamic performance?

The Tesla here looks like an early Lotus Elise/Exige in terms of body shape and size - sans a front intake. This type of shape was okay for the Elise/Exige because these weren't marketing a 250mph+ top speed or anywhere close. Indeed the short wheel base of these cars made them unsuited to those high speeds anyway. Which is another point - this Tesla seems to have a short wheel base also - which further makes me wonder about the 250+ claim.

I'm trying really hard not to take a dump on the Tesla though as I do like them. I'm sure they know more than me and that the info they've released is very early days and designed to generate interest.

The Tesla social media team is particularly active this quarter.

“The first supercar to set every performance record and still fit seating for four.”

Where are the remaining two seats?

Let’s be honest here, at $200k you’ve sold your first born anyway, so does it really matter?

Probably in the glove compartment.

In the back.

They're likely "insurance seats" suitable only for a backpack or duffel bag as is typical for performance cars.

Probably with the 3rd row of the Model Y.

What's the mile range at 250mph?

Also, that picture look cartoon-ish... I wonder if it was modified in any way?

You probably achieve the stated range at ~65MPH. Range decreases approximately with the square of the speed, so range at top speed would be around 16 times lower.

> You probably achieve the stated range at ~65MPH.

got a quote to back that up?

No, it comes from personal experience with Tesla’s other cars.

Note that the listed range comes from a standardized EPA test cycle. It’s more thorough than just cruising at 65MPH but the end result appears to approximate that.

The Bugatti Veyron fuel tank lasts about 12 minutes at 250mph

Since the car produces 10.000Nm, I estimate the peak output power is around 1500kW. So at full power it could drain the 200kWh battery in about 8 minutes. In 8 minutes you will have covered ~33 miles @ 250mph.

Of course there are many other factors at play here.

For comparison: a Bugatti Chiron/Veyron is known to empty its 100L fuel tank in about 12 minutes at full power.

> Also, that picture look cartoon-ish... I wonder if it was modified in any way?

I think it's pretty much a given that a photo has been shopped unless they specifically say it hasn't. Even then one should be skeptical.

But I agree, the degree of post processing in the photo makes it look completely artificial.

Yes, please.

I've loved Tesla Roadsters since "Nash Bridges".

The convertible roof STORES IN THE TRUNK? That is just an absurdly non-luxurious design decision.

Wait you even have to physically remove it ???

Yes, like most convertible supercars/hypercars. The Pagani Huayra, all the Koenigseggs, the LaFerrari Aperta, Bugatti Veyron Grand Sport, etc.

You mean you have to use your foot to operate the gas pedal?! Man Tesla is really going downhill

BMW, Mercedes, and Lexus, and probably other luxury brands made the same choice. I agree it has drawbacks, but it seems already established as a luxury norm.

*sports norm.

Luxury cars are en entirely different class of vehicle, where I doubt this would ever go.

Sports cars tend to be neither luxurious, comfortable nor practical.

One of the many reasons that I never understood why one would buy something like a new Lamborghini Huracan, when you for a similar price could be looking at a Rolls Royce Phantom.

Sports cars are a specialized good, by nature. You're explicitly deciding to sacrifice some things in favor of some other thing (in this case performance). The people you are going to sell it to are therefore exactly the people that are willing to make that sacrifice, the people that just wanna go really friggin fast

Why would you buy a Rolls Royce Phantom? They're boring and don't hold their value.

Because it is far superior to any italian sports car on any parameter that matters outside of a track.

If you want a great car (we are of course ignoring fuel costs here), it is the most comfortable thing you'd ever park your buttocks in, and a much more well thought out vehicle. The usual Lamborghini or Ferrari would in comparison feel like a Peugeot 104 on a good day.

If you want to turn heads, this certainly does it better (although a Lamborghini or Ferrari is likely to get more attention from kids).

Sure, a Huracán has a faster 0-100, but if you want to enjoy the car outside of the track, it would be awful to drive in. Plus, it's still slower than a much cheaper production sedan (Tesla Model S P100D Ludicrous). If you're not going to be the fastest anyway, you might as well be the most comfortable.

None of these high-end vehicles hold their value anyway. Hell, there are really no new vehicles that hold their value. Only classics do.

You seem to be a bit out of touch. I'll leave it at that.

Each to their own.

The specific design is quite different but that's the approach Honda took with their sorta-convertible Del Sol in the 90s. It's not a big deal but it does make you make a conscious physical action and it's a bit of a scramble if it starts to rain.

ADDED: As others have noted, trunk storage is fairly common although it's usually not manual.

Had this with an MR2 I used to own.

The Corvette does the same thing. https://www.cars.com/articles/your-corvette-has-a-removable-...

This is the norm for supercars and hypercars. I listed a few in a comment further down. https://news.ycombinator.com/item?id=20459194

I want one of those

0-60 in under 2 seconds is really dangerous!

somebody get me a new shirt! ... And a new keyboard... . These are all covered in man drool... . I'd pour hot grits in my pants for one of these

I call bullshit on this. 1000km range and 400km/h top speed?

Obviously you can't have both but each of this is unrealistic enough on its own.

You can't even go 400km/h on the Autobahn, which roads are they building this for?

And fully loaded SUVs like the Hyundai Kona get somewhat about 500km in normal crusing mode. 1000km is either a breakthrough in battery technology or measured/calculated when going 50km/h at best.

Unrealistic values imho, but I'm open to be proven otherwise.

Range is easy: just add more battery. It’s expensive, but this is an expensive car.

But space and weight are limited on a supercar. So you have to choose one.

They have a lot to work with since their competitors have to carry V10, V12 and W16 engines

Not if you’re battery-limited in performance. An ideal performance electric car is all battery and motor with the weight of everything else reduced as much as possible. That naturally means your battery will be way over-sized compared to a typical electric car.

Electric batteries are power-limited as well as energy-limited. So if you want more power, you need a bigger battery. (Alternate chemistries are also possible, but even then you reach a practical limit.)

The naive approach is to think of a battery like a gasoline tank, whose size and capacity you want to minimize if you’re going for performance records. But really it’s part of of the powertrain, and having a larger battery brings a bunch of other benefits like longer lifetime (in miles driven), charge & discharge speed (in kilowatts), higher thermal mass (can handle those big spurts of power that might temporarily exceed the cooling system’s capacity), and higher electrical efficiency at a given discharge speed (a larger battery at a given voltage has lower internal resistance, thus less resistive losses and less heat generation).

Space is no problem. Make the floor a bit thicker, done. Look at how much space the battery takes up in other Teslas... if you can find it.

Added weight is not desirable but it’s not a dealbreaker.

Speed / power is a similar affair; a bigger battery is essentially more battery cells, and more power. The increased weight doesn't significantly detract from top speed, as air resistance dominates. In fact, additional weight increases down-force on the road, and thus the maximum force the wheels can apply.

>You can't even go 400km/h on the Autobahn, which roads are they building this for?

They're competing against ferrari/lamborghini/mclaren. The top speed is for the track, not the street. That should be quite obvious....

> I call bullshit on this. 1000km range and 400km/h top speed?

The range is clearly not based on going the top speed for the duration. The distance Tesla gives is typically based on a combined city/highway driving profile. They also provide calculators to estimate your range bssed on the mixture as well as a map program that tells you where you'd need to charge getting from point A to point B if you're going on a long-distance trip.

https://www.tesla.com/trips/

400 km/s is possible on the Autobahn ... but it is an exception.

1000km range at 100km/h maybe :D

> 400 km/s is possible on the Autobahn ... but it is an exception.

Voyager 1 hardly achieves 16.49 km/s. It seems strange that German engineering can achieve better from tarmac & ICE.

/snark

> You can't even go 400km/h on the Autobahn

Yes, you can actually: https://www.motor1.com/news/264061/bugatti-veyron-speed-reco...

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