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Tesla Roadster

tesla.com

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Re: Tesla Roadster

#521

Post by _ea1k »

ygra wrote: post #166
kijin wrote: post #144

Earlier quoted context omitted.

I wonder what happens when one of these cars crashes head-on into something. The front of a car is supposed to act as a crumple zone. Batteries aren't very good at crumpling.

Neither are internal combustion engines. What crumples are structural supports, not all the components within. And if they go that route I guess they'll go with slightly different battery chemistry as well to avoid a fire. They might have to do so anyway to sustain power output.

Yeah, and Tesla has talked about this extensively in the past. It would be pretty surprising if they switch to using this area for battery, but it is possible.

Re: Tesla Roadster

#522

Post by drcoopster »

Siecje wrote: post #490
in3d wrote: post #365

Earlier quoted context omitted.

Sounds really good on paper but the production is scheduled for 2020, so it’s unfair to compare it to the cars currently on the market. No other manufacturers announce cars so far ahead so it seems at least partly like a hype for Tesla investors. Acceleration is just one part of what makes a great sports car. And how is the acceleration past 100 mph? That’s the traditional weakness of electric cars and it matters mor…

> And how is the acceleration past 100 mph? I thought the instant torque was able to get great acceleration at all speeds?

The torque drops off as the motor RPM increases.

Re: Tesla Roadster

#523

Post by mcguire »

Unklejoe wrote: post #480

Has the 8 second quarter mile been confirmed to be done in stock trim (i.e., no special tires or other modifications)? The reason I ask is because that is EXTREMELY impressive. I tune EFI systems on race cars as a hobby, and any car in the 8 second range usually needs to run slicks or drag radials to have enough traction. Even all wheel drive cars (GTRs, DSMs, EVOs, etc.) usually run 4 slicks once they get to that sp…

I was wondering that myself after seeing the 1.9s 0-60 time. My understanding was that anything under 2.5s was the domain of racing slicks and sticky compounds.

Re: Tesla Roadster

#525

Post by fhood »

neom wrote: post #511
Unklejoe wrote: post #480

Has the 8 second quarter mile been confirmed to be done in stock trim (i.e., no special tires or other modifications)? The reason I ask is because that is EXTREMELY impressive. I tune EFI systems on race cars as a hobby, and any car in the 8 second range usually needs to run slicks or drag radials to have enough traction. Even all wheel drive cars (GTRs, DSMs, EVOs, etc.) usually run 4 slicks once they get to that sp…

I'll be amazed, amazzzzed , if that car, stock, can create enough down force to keep itself on the road with stock tires, I don't care how good your TC is. Look at the size of the wing on the new Zr1 https://youtu.be/O_adY_b-aLQ?t=3m14s

Wing shouldn't matter all that much in this case. Grip is most important in the initial moments of acceleration on the drag strip where having a wing isn't quite as important. This car[1] runs in the 7s without a wing at all.

[1] http://st.hotrod.com/uploads/sites/21/2017/09/149-test-tune-...

Re: Tesla Roadster

#526

Post by Robotbeat »

balfirevic wrote: post #504
InternetOfStuff wrote: post #411

Earlier quoted context omitted.

Honest question: did you just make up these numbers, or are they based in fact? I was expecting the motor to turn slower.

Not OP, but Tesla Model S has approximately 1:10 fixed gear reduction. Motor RPM will go higher than 10000 RPM at really high speeds.

Right. And electric motors are more efficient at higher RPMs. At high RPM, the voltage drop due to back-EMF (i.e. actual work) is higher but your voltage drop due to coil resistance is about the same, so you lose proportionally less energy in the form of coil resistance at higher rpm.

Re: Tesla Roadster

#527

Post by efraim »

jpitz wrote: post #326
Jdam wrote: post #67

Earlier quoted context omitted.

> No exotic carmaker will be able to match it. Did you fact check that? Actually, Bugatti is pretty close and partially outperforms, although at a way higher price point. https://en.wikipedia.org/wiki/Bugatti_Chiron

The Chiron is an order of magnitude more expensive, and still fails to be quicker.

But the Chiron exist today.

Re: Tesla Roadster

#528

Post by fhood »

mcguire wrote: post #523
Unklejoe wrote: post #480

Has the 8 second quarter mile been confirmed to be done in stock trim (i.e., no special tires or other modifications)? The reason I ask is because that is EXTREMELY impressive. I tune EFI systems on race cars as a hobby, and any car in the 8 second range usually needs to run slicks or drag radials to have enough traction. Even all wheel drive cars (GTRs, DSMs, EVOs, etc.) usually run 4 slicks once they get to that sp…

I was wondering that myself after seeing the 1.9s 0-60 time. My understanding was that anything under 2.5s was the domain of racing slicks and sticky compounds.

The car in the image has some monster tires on it. Doesn't give you the compression (or whatever you use to describe the give in the tire) friction you get with serious drag tires, but with a good four wheel drive system?

Re: Tesla Roadster

#530

Post by neom »

fhood wrote: post #525
neom wrote: post #511

Earlier quoted context omitted.

I'll be amazed, amazzzzed , if that car, stock, can create enough down force to keep itself on the road with stock tires, I don't care how good your TC is. Look at the size of the wing on the new Zr1 https://youtu.be/O_adY_b-aLQ?t=3m14s

Wing shouldn't matter all that much in this case. Grip is most important in the initial moments of acceleration on the drag strip where having a wing isn't quite as important. This car[1] runs in the 7s without a wing at all. [1] http://st.hotrod.com/uploads/sites/21/2017/09/149-test-tune-...

Fair! That said, I do doubt those cars weigh close to the same. :)
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