RE: Tesla 'Ludicrous Mode' introduced

[ging84]

0-60 in 2.8 seconds
in a car which weights as much as a range rover and cost less than £90k
just think what we will be able to expect in 5 years time when battery weights and costs are expect to be down 20-30%

[MrTappets]

Can anyone explain to me why the Model S is so much less accelerative at, say, 100mph than other cars with the same peak horsepower? Is it just that the Tesla is geared in such a way that it's making far less than peak at those speeds?

[red997]

I've lined up against a Tesla at Bruntingthorpe;

He had a slight jump in front on lift off, and was in front for about a second before we passed him; after that I didn't see him

Very, very impressive - I like the way electric power is going - just need a more efficient power source and charging speed, and it will be there.

(BTW is was in my modified Panamera turbo, using launch control )

[R8VXF]

MrTappets said:

Can anyone explain to me why the Model S is so much less accelerative at, say, 100mph than other cars with the same peak horsepower? Is it just that the Tesla is geared in such a way that it's making far less than peak at those speeds?

AFAIK it is direct drive. If you look at the dyno graph you can see that the torque drops off rapidly past a certain point causing a flat power line. Compare that to a S/C V8 and the power line climbs all the way to the red line with a far smaller drop off in torque meaning acceleration is maintained:

[Ved]

But will it take off?

[kambites]

R8VXF said:

AFAIK it is direct drive. If you look at the dyno graph you can see that the torque drops off rapidly past a certain point causing a flat power line. Compare that to a S/C V8 and the power line climbs all the way to the red line with a far smaller drop off in torque meaning acceleration is maintained:

Well yes but with an ICE powered car you'd be changing gear to try to stay near peak power and you'd fail - at any given speed above the point where the power curve levels out, the Tesla will be putting out at least as much, and typically more, torque at the wheels than a geared ICE powered car with the same peak power.

Flywheel torque means nothing.

[lockup]

Impasse said:

0.01 rpm is rotating and therefore not the 0 rpm often quoted as some sort of wonder stat. 0 rpm is of no use if you wish to move the vehicle.
Mind you, neither is a failing National Grid which predicts there may be electric blackouts this winter. But that's another story altogether.

Oh dear.

All vehicles can apply torque to the driven wheels at a standstill. If they didn't they wouldn't pull away. Electric motors can deliver a relative large amount. They have no need for smokey clutches or slushy torque convertors because they can deliver that torque at 0 rpm.

Next.

[Talksteer]

JMF894 said:

Well it's not as if it wasn't fast enough to start with. Perhaps they should concentrate on making it go further rather than faster, and charge quicker?

Jimbo

As others have said the Tesla battery it's getting 5% larger each year.

On average batteries are getting around 10% "better" each year. Though that would be a product of power density and cost.

To put that into perspective that would involve batteries doubling in power density/cost every 8-14years.

I'd argue that a 300mile range (even if it's 200 miles in practice) is easily enough that it will be relatively rare that you'd travel further than that in a single day and you can just charge it slowly over night. Therefore bringing the cost down is probably more important.

If you're going a long way stopping every 200 miles to use the super charger for 30 minutes is hardly an impediment.

[glazbagun]

Awesome stuff, I really like they way Tesla are going

I really can't wait for Teslas to filter down to levels Golf/Focus buyers can afford. Electric power doesn't seem to have the large tradeoff between peak performance and peak economy that IC engines do.

Sadly I also think they'll be the beginning of the end for a lot of fun motoring as I can't see the govermnemt allowing every next prole an 11 second 1/4 mile. The money they lose from fuel revenue will end up being stacked onto insurance as tax.

Out of curiosity, I know that F=MA and thus greater acceleration requires greater force. But in a 0-60 sprint you're be accelerating for less time as you hit your desired speed sooner. So (assuming a block sitting on a frictionless surface) what is the relationship between acceleration and total energy consumption in a 0-60 sprint??

Does twice the force for half as long consume as much as half the force for twice as long?

[R8VXF]

Talksteer said:

JMF894 said:

Well it's not as if it wasn't fast enough to start with. Perhaps they should concentrate on making it go further rather than faster, and charge quicker?

Jimbo

As others have said the Tesla battery it's getting 5% larger each year.

On average batteries are getting around 10% "better" each year. Though that would be a product of power density and cost.

To put that into perspective that would involve batteries doubling in power density/cost every 8-14years.

I'd argue that a 300mile range (even if it's 200 miles in practice) is easily enough that it will be relatively rare that you'd travel further than that in a single day and you can just charge it slowly over night. Therefore bringing the cost down is probably more important.

If you're going a long way stopping every 200 miles to use the super charger for 30 minutes is hardly an impediment.

Having driven the 800ish miles home from Scotland in a day recently in a car that has a 300ish mile range, adding an extra hour and a half onto the journey would have been a deal breaker

[glazbagun]

R8VXF said:

aving driven the 800ish miles home from Scotland in a day recently in a car that has a 300ish mile range, adding an extra hour and a half onto the journey would have been a deal breaker

Whenever I've done the trip (only ~450 miles for me) I've usually had to stop at least twice. Even if you average 80MPH on a good day that't ten hours sitting in a car, surely you'd need a couple of Burger Kings along the way?

[R8VXF]

glazbagun said:

R8VXF said:

aving driven the 800ish miles home from Scotland in a day recently in a car that has a 300ish mile range, adding an extra hour and a half onto the journey would have been a deal breaker

Whenever I've done the trip (only ~450 miles for me) I've usually had to stop at least twice. Even if you average 80MPH on a good day that't ten hours sitting in a car, surely you'd need a couple of Burger Kings along the way?

I ate sandwiches whilst driving. Never stopped for more than 10-15 minutes at a time. The GTS cruises so well that you don't need to stop for very long or very often. Have done penzance to reading in a single run with no stops recently as well. Car was running on fumes by the time I reached home admittedly. Think I averaged 83mph or there abouts.

[greygoose]

I've being seeing quite a few more Teslas about recently and last week they installed four charging points at work so it does make it quite tempting if they built something a bit smaller.

[Carparticus]

red997 said:

I've lined up against a Tesla at Bruntingthorpe; He had a slight jump in front on lift off, and was in front for about a second before we passed him; after that I didn't see him

That would not have been one of the "quick" ones!! There are no privately owned P85Ds in the UK yet, let alone the daft version announced last week.

The 'Ludicrous' Tesla does 0-60 in 2.8s, 0-100 in 7s, and a standing quarter in 10.8s.


Whilst its not a track car in any sense of the word, those figures are impressive if you only want to dump that much power once or twice on the trot. To put the ss qtr figure into perspective :-

[Chris Wilson]

Technically interesting, but utterly impractical for most users. Plus they just move the pollution somewhere else, people think the electrons coming out of power sockets are made in fairyland, when in reality their manufacture is costly and dirty. People tut and mutter if there's a queue of 6 people at the petrol station till, God knows how they would react to an age awaiting the Charge `O' Meter creeping up, assuming there's one at their destination or en route, that is in use for an age, before even commencing your own car's charge.

Now, when we have fought IS, battled Ebola, repelled the invaders in the Channel Tunnel, waged civil war, and the population of the civilised world is decimated to a sustainable level, all this junk will be irrelevant, and the survivors can rape the remains of the planet without a care

Edited by Chris Wilson on Monday 20th July 15:59

[Sheepshanks]

Carparticus said:

The 'Ludicrous' Tesla does 0-60 in 2.8s,

That's the same time as Disney's Rock'n'Roller Coaster gets to 57MPH. Once was enough!

[Toltec]

lockup said:

Oh dear.

All vehicles can apply torque to the driven wheels at a standstill. If they didn't they wouldn't pull away. Electric motors can deliver a relative large amount. They have no need for smokey clutches or slushy torque convertors because they can deliver that torque at 0 rpm.

Next.

Pretty much what I was thinking too, getting confused with engine rpm and what matters, i.e. wheel rpm/torque.

Ignoring the driving feel, torque converters are very good at applying high torque to the wheels at low wheel rpm.

[AMG Merc]

They had one going up the hill at Brooklands yesterday. It was jaw-dropping amazing (electric even!) I timed his 2nd run at 5.9s and then the following at 5.2s. I'd say he was the fastest there.

[Joeguard1990]

Sheepshanks said:

That's the same time as Disney's Rock'n'Roller Coaster gets to 57MPH. Once was enough!

There is a ride at Alton Towers that is a lot quicker than the one at Disney called "Rita".

61.1mph in 2.5 seconds.

And if you think that's fast, go to Thorpe Park where they have a similar one called "Stealth"

0-80mph in 1.8 seconds!!!

[ikarl]

I think there could be a breakthrough when electric driverless cars start hitting the streets.

A car that can drive itself more efficiently than us ‘squishy blobs’ should be interesting. I wonder how many miles a computer controlled electric car could achieve.