5% Power Increase = ???

[seantay00]

Has there been an math or extrapolation regarding what a 5% power increase would tangibly drive? I've heard speculation of .1 sec of 0 to 60 time across the board, but wasn't sure what this might be based off of....

 

[run-the-joules]

Has there been an math or extrapolation regarding what a 5% power increase would tangibly drive? I've heard speculation of .1 sec of 0 to 60 time across the board, but wasn't sure what this might be based off of....

…the numbers Tesla supplied, for a start?

 

[AlanSubie4Life]

There are various threads already with related discussion.

5% increase in power

Perf gets higher top speed, RWD more range, but no love for AWD???


EDIT: Elon and Tesla have stated a firmware upgrade scheduled for March 15th will apply the change. So you should have it by sometime in May.

 

[seantay00]

…the numbers Tesla supplied, for a start?

I haven't seen any date from Tesla on M3 AWD (non-P) and site still shows the same. Did I miss something?

 

[StellarRat]

It's a squared function, .1 is the closest answer. So you estimate is accurate. Of course, you can also confirm it against Tesla's number which are in agreement.

 

[gilscales]

5% peak power would be close to an extra 17hp on a LR RWD model

Based on MPP dyno of peak 335hp

Would be interesting to see another dyno pull over 350 peak hp

 

[SageBrush]

Has there been an math or extrapolation regarding what a 5% power increase would tangibly drive? I've heard speculation of .1 sec of 0 to 60 time across the board, but wasn't sure what this might be based off of....

Power is proportional to acceleration,
and velocity = acceleration * time

So if acceleration increases 5%, time decreases 5%

If a current LR Model 0-60 is 5.3 seconds, after the upgrade it will be 5.3/1.05 = 5.048 seconds

 

[alienranch]

Power is proportional to acceleration,
and velocity = acceleration * time

So if acceleration increases 5%, time decreases 5%

If a current LR Model 0-60 is 5.3 seconds, after the upgrade it will be 5.3/1.05 = 5.048 seconds

This is crazy flawed. Power is up 5%, not acceleration. A percentage increase in power is not proportional to the same increase in acceleration. Not even close.

 

[SageBrush]

This is crazy flawed. Power is up 5%, not acceleration. A percentage increase in power is not proportional to the same increase in acceleration. Not even close.

The energy invested in moving a car from 0 - 60 is ~ a combination of kinetic energy, road resistance, and aero forces acting on the car. Car power increases do not change that amount, which we will call W(ork).

Power * time = work
Since work is ~ constant, power and time are inversely proportional.

At least so my HS level physics tells me.

 

[alienranch]

The energy invested in moving a car from 0 - 60 is ~ a combination of kinetic energy, road resistance, and aero forces acting on the car. Car power increases do not change that amount, which we will call W(ork).

Power * time = work
Since work is ~ constant, power and time are inversely proportional.

At least so my HS level physics tells me.

Assuming you're not trolling, there is a point of diminishing returns that anybody who understands performance cars knows about. My 460hp Corvette does 0-60 in something like 3.4 seconds. My 650 hp Viper does 0-60 in about 3.1 seconds, yet it has about 40% more power. By your calculations my Viper should be hitting 60 in the low 2 seconds which is ridiculous. Same goes for top speed. Corvette does something like 190 but my Viper tops out at 208. Shouldn't it top out at almost 270 by your linear calculations? None of this takes into account the countless variables in determining acceleration and top speed, none of which obey you direct 1:1 correlation between power increase and acceleration increase. This is so basic and widely understood that I honestly can't tell if you're trolling, or perhaps need to take a more advanced physics course than just high school.

 

[mongo]

Power is proportional to acceleration,
and velocity = acceleration * time

So if acceleration increases 5%, time decreases 5%

If a current LR Model 0-60 is 5.3 seconds, after the upgrade it will be 5.3/1.05 = 5.048 seconds

This is crazy flawed. Power is up 5%, not acceleration. A percentage increase in power is not proportional to the same increase in acceleration. Not even close.

SageBrush is correct:
Force = mass *acceleration
Force = electrical power (watts)* motor conversion factor
A 5% increase in peak power is a 5% increase in peak force, is a 5% increase in acceleration for the same mass, is also a 5% increase in velocity vs time.
However, in terms of a quarter mile, or other distance calc (ignoring rolling and aero):
position = 1/2*a*t^2, so with a 5% increase in a, the time to reach a specific distance changes by ~2.5%.

 

[alienranch]

SageBrush is correct:
Force = mass *acceleration
Force = electrical power (watts)* motor conversion factor
A 5% increase in peak power is a 5% increase in peak force, is a 5% increase in acceleration for the same mass, is also a 5% increase in velocity vs time.
However, in terms of a quarter mile, or other distance calc (ignoring rolling and aero):
position = 1/2*a*t^2, so with a 5% increase in a, the time to reach a specific distance changes by ~2.5%.

That's already significantly cutting into SageBrush's time, which is exactly what I'm saying. If you're going to use physics calculations to determine an outcome, you can't pick and choose what variables you want to include. He's excluding numerous factors ranging from rolling resistance, wind resistance (which increases exponentially), traction, traction management and slippage, ability to supply the power (injectors, intake, etc for ICE, and discharge rates for EV), and a host of other factors honestly far in excess of my knowledge. It doesn't take a rocket scientist to understand this. a typical 500hp sports car hits 60 in the mid 3 second range. Does anyone really think a 900hp car does the same thing in .7 seconds? Power increase and acceleration are absolutely related, but not linear (1:1) in the real world.

 

[SageBrush]

Tesla is advertising the 0 - 60 time of the Model 3 LR as 5.0 seconds. IIRC it was 5.3 seconds before the firmware upgrade.

 

[juanmedina]

SageBrush is correct:
Force = mass *acceleration
Force = electrical power (watts)* motor conversion factor
A 5% increase in peak power is a 5% increase in peak force, is a 5% increase in acceleration for the same mass, is also a 5% increase in velocity vs time.
However, in terms of a quarter mile, or other distance calc (ignoring rolling and aero):
position = 1/2*a*t^2, so with a 5% increase in a, the time to reach a specific distance changes by ~2.5%.

If that's the case that would be huge for 1/4th mile times.

 

[SageBrush]

That's already significantly cutting into SageBrush's time, which is exactly what I'm saying. I

You are misunderstanding Mongo. The percent reduction in time for a distance trial is the square root of that seen in a speed trial.

 

[TANGO SUKKA]

so 5% on a p3d is 5% more top speed? acceleration? horsepower? all of the above?

 

[SageBrush]

, there is a point of diminishing returns that anybody who understands performance cars knows about. My 460hp Corvette does 0-60 in something like 3.4 seconds. My 650 hp Viper does 0-60 in about 3.1 seconds, yet it has about 40% more power.

An electric car reaches peak power sooner than an ICE, and stays there. This is why EVs keep dusting uninformed ICE drivers on the track despite having lower peak power ratings.

 

[alienranch]

An electric car reaches peak power sooner than an ICE, and stays there. This is why EVs keep dusting uninformed ICE drivers on the track despite having lower peak power ratings.

Of course it reaches peak power faster than an ICE, but that has absolutely nothing to do with the direct 1:1 correlation you're asserting.

 

[Garlan Garner]

Has there been an math or extrapolation regarding what a 5% power increase would tangibly drive? I've heard speculation of .1 sec of 0 to 60 time across the board, but wasn't sure what this might be based off of....

math = multiply distance by 1.05.

math = multiply everything by 1.05.

I'm not sure why its more complicated than that.

 

[SageBrush]

Of course it reaches peak power faster than an ICE, but that has absolutely nothing to do with the direct 1:1 correlation you're asserting.

I was pointing out the greater discrepancy between peak power and average power in your ICE cars to explain your experience. If you knew the average power increase in your beefier car you would find that the improvement in race times is ~ proportional.