551–560 of 729 posts
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Think of it this way, if some server or database came out claiming incredible benchmark numbers you’d say okay now show me some real world workloads. Same here. 0-60 is an artificial benchmark, a circuit time is a real world workload.
They already have a test car: https://www.youtube.com/watch?time_continue=3380&v=aXWfL-1ie... I'm pretty sure they aren't making it up.
Don't get me wrong it's a deeply impressive vehicle. I'm just not an Elon fanboy and the precise milisecond that what Porsche, McLaren et. al. customers want something like that is when they will start making it. It's not like one company is the future and the rest of them are dinosaurs. One company is small and loosing money and the others are making it, enough of it to buy Tesla any time they feel like it, which being realistic is what's going to happen eventually.
Am I the only one who's worried that Tesla is really starting to bite off more than they can chew? Right now their finances are a mess, they are publicly struggling to produce their most important car ever, their CEO is spending time figuring out how to dig holes underneath LA...and now they're announcing a semi truck and a roaster in the same day? Don't get me wrong, Teslas are incredible cars. But this seems like a…
You have been reading too many finance blogs. Their finances are far from a mess, they are just not what finance people like to see. They have cash on hand and a roadmap to execute on. If they don't execute they will go out of business, and they will take my money as an investor with them. I'm OK with that and as long as they continue to have a path to profitability I am all on board. I want to see them burning money…
Isn't this part of not executing the roadmap as planned? Put another way, how do you know if they are on the right trajectory to profitability? How much are they ahead/behind?
Am I the only one who's worried that Tesla is really starting to bite off more than they can chew? Right now their finances are a mess, they are publicly struggling to produce their most important car ever, their CEO is spending time figuring out how to dig holes underneath LA...and now they're announcing a semi truck and a roaster in the same day? Don't get me wrong, Teslas are incredible cars. But this seems like a…
Yes. It is only human to be worried. They lose money on every car they sell. And the losses are accelerating. If you bought $TSLA at $300. And are looking to hold on for dear life. The next 12-24 months is gut check time. But there is so much to be optimistic about! Uber or Lyft or Didi could place 100K size orders of Model 3s for their driverless fleets, with substantial support contracts, by 2019. Powerwalls may be…
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Isn't the rack-and-pinion for steering, not for power transmission to wheels?
Yes rack and pinion is for steering. Parent may have meant "ring and pinion" which would refer to the differential gear ratio.
I was wondering, because I seemed to connect the expression with steering as well :-) At least I have the excuse of not being a native speaker.
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The OP is right that 8 sec 1/4 is extremely impressive, but he is wrong that there are few production cars that can run 8s. No production car runs anything close. The fastest 1/4 mile production cars are supercars such as the Veyron and 918, which are at or just under a 10seconds. Remember, an increase from 20->18 seconds is roughly a 10% increase in acceleration; 10->8 is roughly 20% increase over an already ludicro…
You're right - I can't find any other car that can run 8's without modifications. There are some that can achieve those numbers with under $10,000 worth of modifications, but that's kind of irrelevant since we're talking about stock cars. That's also why I am skeptical of this Tesla running an 8 second pass in stock trim. Is there a video of the pass? Most of the 8 second cars I've seen are running slicks or drag rad…
Can you provide links? I seriously doubt you can get anything into the 8s with only $10k.
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I can't find better than 2.28 seconds documented. http://www.motortrend.com/cars/tesla/model-s/2017/2017-tesla...
The parent just wanted to point out that braking is just as fast as accelerating. They didn't mean to say that the Model S can accelerate as fast as the new Roadster.
Being traction limited 0-60 is nothing new for high performance sports cars, the difference is that using an electic motors, the power output can be modulated on a millisecond by millisecond basis. So the electric car can live on the ragged edge of traction eeking out every last newton. ICE cars on the other hand use motors that throttle responses that are orders of magnitude greater. Restricting how much the the traction envelope they can use. Which is why their 0-60 and 60-0 times tend to be different.
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> F1 tires are nothing like road tires. Agreed, but they don't need to be. Remember, the magic number here is ~1.4G, for a 1.9s 0-60. The Pilot Sport Cup 2 – a track-friendly R-compound tire used in the webcast car and in the videos – can pull close to that on a skidpad (i.e. less than optimal conditions), meaning the grip is there. > I think it's straining credulity to believe that an electronic traction control sys…
> Agreed, but they don't need to be. Remember, the magic number here is ~1.4G, for a 1.9s 0-60. The Pilot Sport Cup 2 – a track-friendly R-compound tire used in the webcast car and in the videos – can pull close to that on a skidpad (i.e. less than optimal conditions), meaning the grip is there. That's lateral grip, which isn't the same at all. Longitudinal grip, which is what's important here, is very different. The…
Camber isn't a magical trick to get more grip; it's a way to restore grip that would otherwise have been lost because of uneven tire loading in a corner. In a straight-line drive situation, the load is already ideal; the contact patch is the maximum size and fairly evenly distributed across the width of the tire.
> There is just no way you can make a road car that's faster than an LMP1 hybrid.
Indeed, it's currently impossible to make an all-electric race car that can compete with an ICE or hybrid race car in general race conditions, mostly because of the limitations of the energy storage. If the goal is just for a road car to beat a hybrid LMP1 (or even F1) car in a drag race though, as is the case here, I think that's much more doable. The ICE is really the weak link there.
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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.
How big is the difference?
It must be pretty substantial to offset both friction losses and gearing efficiency.