5% increase in power

[AlanSubie4Life]

Curious what your source is for that because I actually every physics textbook that I've ever consulted about this says that your power consumption is proportional to the square of your velocity cuz most of it is actually drag. And that's proportional to Velocity squared not cubed. Has data against the cubed supposition, I can measure my Watt hours per mile at 40 miles an hour and depending on temperature at somewhere between 180 and 190 Watt hours per mile and it is exactly doubled at 80 miles per hour. This is not possible if your formula is correct.

Force required to overcome drag goes up with square of velocity. So force, and thus work (energy) for a fixed distance go up with the square of velocity. However, since you get there faster (time inversely proportional to velocity), and therefore the work is done faster, and power is the rate of producing work, the resulting required power goes up as the cube of velocity. But energy required from point A to B would scale with the square.

So your Wh/mi numbers are correct and scale with the square, but required power goes up with the cube of velocity.

 

[dfwatt]

Force required to overcome drag goes up with square of velocity. So force, and thus work (energy) for a fixed distance go up with the square of velocity. However, since you get there faster (time inversely proportional to velocity), and therefore the work is done faster, and power is the rate of producing work, the resulting required power goes up as the cube of velocity. But energy required from point A to B would scale with the square.

So your Wh/mi numbers are correct and scale with the square, but required power goes up with the cube of velocity.

Excellent and erudite explanation Alan. You must be somewhere in the Sciences. I recognize the signs and symptoms

 

[Zcd1]

I figured the 155 mph limiter was so Tesla would be aligned with the German mfrs. "155 mph max. gentlemen's agreement for sedans".

Of course, you can pay all 3 of those manufacturers (in Germany) to unlock higher top speeds...

 

[SammichLover]

I unfurled my P3D- yesterday on an AMG that wanted to be first down the freeway on ramp He thought he was going to show off!

In my post the word "generally" is doing a fair amount of work.

 

[ElectricGhost]

So 473 HP/495 torque now?

So anyone know if P3D- gets the power boost too?

I don’t expect it to get the top speed increase but really thans not very useful anyway outside a race track or going full idiot on the autobahn.

 

[caskater47]

So anyone know if P3D- gets the power boost too?

I don’t expect it to get the top speed increase but really thans not very useful anyway outside a race track or going full idiot on the autobahn.

There's no reason why the Stealth won't get both. The press release clearly states "Model 3 Performance". Since it did not specify a particlular trim or config then it must be both.

 

[lbowroom]

Yes, but...

 

[MagnusMako]

1. Everyday Astronaut‏ @Erdayastronaut Mar 2
   Wait. So all performance model 3’s will get a software update to increase top speed, or acceleration (or both) AND the range is getting increased too???
   
   14 replies14 retweets923 likes
   

Elon Musk‏Verified account @elonmusk
Replying to @Erdayastronaut @causal_mind @nico_rosberg
Power will increase on all cars.

All cars = all model 3's.


Elon Musk on Twitter

 

[Oyinko]

Do we know with software update includes the 5% increase?

 

[diamond.g]

Do we know with software update includes the 5% increase?

Supposed to be 2019.5.15, though no one has done an instrumented test (read dyno) to confirm yet.

 

[Knightshade]

Supposed to be 2019.5.15, though no one has done an instrumented test (read dyno) to confirm yet.

This suggests otherwise-
Performance improvements with latest update? (AWD) : teslamotors

 

[diamond.g]

This suggests otherwise-
Performance improvements with latest update? (AWD) : teslamotors

Yeah, I saw that. To be fair they also loss power going from 5.4 to 5.15 (or at least that is what the API reports). They are also getting an additional ~20hp over what we saw on the dyno comparison between the D and P.

Someone else pointed to a tweet from Elon stating the power and range increase will be coming later in the month, even though some folks are seeing the range change now.

 

[dave999z]

1. Everyday Astronaut‏ @Erdayastronaut Mar 2
   Wait. So all performance model 3’s will get a software update to increase top speed, or acceleration (or both) AND the range is getting increased too???
   
   14 replies14 retweets923 likes
   

Elon Musk‏Verified account @elonmusk
Replying to @Erdayastronaut @causal_mind @nico_rosberg
Power will increase on all cars.

All cars = all model 3's.


Elon Musk on Twitter

So, does "5% power increase" on all cars mean 0-60 improvement on all cars?

I presume if there is even one or two tenths of a second shaved off, they will update this on the website specs. I think 0-60 times is a huge selling point for many people, and many do consider tenths to matter.

 

[Nocturnal]

So, does "5% power increase" on all cars mean 0-60 improvement on all cars?

I presume if there is even one or two tenths of a second shaved off, they will update this on the website specs. I think 0-60 times is a huge selling point for many people, and many do consider tenths to matter.

It must be. We have no idea where that 5% is or what it looks like, but it's hard to imagine 0-60 not being impacted.

Supposed to be 2019.5.15, though no one has done an instrumented test (read dyno) to confirm yet.

God forbid Tesla actually communicates this to us. FFS. How are they so bad at this? Send all customers an email explaining how the LR range increase works. Send the rest a note about the performance increase.

Getting news from Tesla via Elon's twitter is like drinking from a straw, and the cup is full of vodka. ​

 

[dave999z]

Getting news from Tesla via Elon's twitter is like drinking from a straw, and the cup is full of vodka. ​

Where's the bad part?

 

[dfwatt]

So, does "5% power increase" on all cars mean 0-60 improvement on all cars?

I presume if there is even one or two tenths of a second shaved off, they will update this on the website specs. I think 0-60 times is a huge selling point for many people, and many do consider tenths to matter.

I would also assume so . . .but then again, this is Tesla after all! 5% probably translates into just over 3 sec or perhaps 3.05 from 3.2.

 

[AlanSubie4Life]

I would also assume so . . .but then again, this is Tesla after all! 5% probably translates into just over 3 sec or perhaps 3.05 from 3.2.

Would not get your hopes up for that number on a stock Performance vehicle. If they increase torque all the way up it will be awesome. But they're just increasing power. And unless they are hiding something the specs on the website are presumably correct (3.2 for the Performance not including rollout - it used to be 3.3 not including rollout).

Remember the peak HP increase only makes a difference above about 45mph (assuming no torque increase). 45-60mph takes 1.2 seconds or so right now. Maybe expect that to be dropped to 1.1 seconds at best. Nothing changes from 0-45mph since there's no change there (peak HP makes no difference there since it's not at peak HP currently in that range of speeds).

However, I suppose we can hope for peak torque increase and over-delivery by Tesla in the future. I suspect they're holding back just a little bit more torque to help ensure competitiveness with Porsche/BMW in the next year or so. If necessary and reliability data suggests it is ok, maybe they'll bump by 5% more or something (in torque). Which will reduce the 0-45 time (currently about 2.5 seconds including rollout) by an additional 0.15 seconds or so. (So maybe 0-60 including rollout would be 2.3+1.1 = 3.4 rather than the current 3.6+.) They have not suggested this will happen in the upcoming update though, or ever.

 

[dfwatt]

Would not get your hopes up for that number on a stock Performance vehicle. If they increase torque all the way up it will be awesome. But they're just increasing power. And unless they are hiding something the specs on the website are presumably correct (3.2 for the Performance not including rollout - it used to be 3.3 not including rollout).

Remember the peak HP increase only makes a difference above about 45mph (assuming no torque increase). 45-60mph takes 1.2 seconds or so right now. Maybe expect that to be dropped to 1.1 seconds at best. Nothing changes from 0-45mph since there's no change there (peak HP makes no difference there since it's not at peak HP currently in that range of speeds).

However, I suppose we can hope for peak torque increase and over-delivery by Tesla in the future. I suspect they're holding back just a little bit more torque to help ensure competitiveness with Porsche/BMW in the next year or so. If necessary and reliability data suggests it is ok, maybe they'll bump by 5% more or something (in torque). Which will reduce the 0-45 time (currently about 2.5 seconds including rollout) by an additional 0.15 seconds or so. (So maybe 0-60 including rollout would be 2.3+1.1 = 3.4 rather than the current 3.6+.) They have not suggested this will happen in the upcoming update though, or ever.

Once again Alan excellent and erudite analysis . . .far superior to mine. I was assuming that they might bump torque as well as horsepower but I think you're right it's probably more likely they just extend the torque peak to a somewhat higher RPM

 

[AlanSubie4Life]

Once again Alan excellent and erudite analysis . . .far superior to mine. I was assuming that they might bump torque as well as horsepower but I think you're right it's probably more likely they just extend the torque peak to a somewhat higher RPM

Well, I'm still hoping I'm wrong, of course. But based on what Tesla has said so far... We'll see in a week or two. Or a month or two.

There are still some unknowns here about how long (up to what speed) they hold the new HP peak and whether that changes at all. HP peak doesn't last that long though I know less about that (kind of have to go off the various dyno plots for an estimate, kind of looks like it really starts to drop at about 80mph, but I don't entirely believe the dyno plots, just use them as a rough guide...). The longer the peak holds the better, of course. But that's more at speeds above 50 up to 80mph or whatever. I personally don't care that much at those speeds. Most of the time the power won't be available to me anyway, due to SoC.

 

[usofrob]

It seems like they're waiting to increase the power until after they've launched the Model Y. I wonder if it's related.