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Discussion Starter · #1 ·
So, I sent an email to the Consumer Affairs lady at Fisker asking about the new horsepower ratings now that the 0-60 times have been reduced to 6.3 seconds. Unfortunately, she had no information on the 0-60 in Stealth mode, but she did say that the horsepower and torque numbers remain the same.

I suspect this is true since the car's top speed is still 125mph, but I also suspect this is Fisker playing with the numbers again because we've previously been told that the power has been reduced which resulted in the slower 0-60. The car probably does output 403hp at some point to get it to 125mph, but my guess is that the software limits the horsepower at slower speeds. At 0-60 the horsepower output is probably well less than 400, but they ramp it up at higher speeds.

Dunno... just a guess, but there's no way the HP is the same while the acceleration goes down. Either they were just plain wrong all along, the weight went up, or the HP has been reduced.

-Brian
 

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brian said:
So, I sent an email to the Consumer Affairs lady at Fisker asking about the new horsepower ratings now that the 0-60 times have been reduced to 6.3 seconds. Unfortunately, she had no information on the 0-60 in Stealth mode, but she did say that the horsepower and torque numbers remain the same.

I suspect this is true since the car's top speed is still 125mph, but I also suspect this is Fisker playing with the numbers again because we've previously been told that the power has been reduced which resulted in the slower 0-60. The car probably does output 403hp at some point to get it to 125mph, but my guess is that the software limits the horsepower at slower speeds. At 0-60 the horsepower output is probably well less than 400, but they ramp it up at higher speeds.

Dunno... just a guess, but there's no way the HP is the same while the acceleration goes down. Either they were just plain wrong all along, the weight went up, or the HP has been reduced.

-Brian
I believe that the weight did go up (from a planned number around 5000 to the delivered 5300). That's about a 6% increase, and 5.9 to 6.3 seconds is about a ... 6% increase.[hr]
BTW if you apply the 6% increase to the original Stealth time of 7.9 you get 8.4 seconds.
 

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Discussion Starter · #3 ·
Well, what I was told recently was that the 0-60 time changed because of the new exhaust, the new inverter, and new software. I don't think it had anything to do with weight.

-Brian
 

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Could be. The software won't change the weight of course, but the exhaust system and inverter might. I wonder what they did with the inverter? Is it liquid cooled?
 

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My understanding is that the batteries aren't powerful enough to drive the electric motors at full power on their own (at the motor's full HP), and that's why the engine has to be running in Sport mode. Now that they've had to reduce the power of the engine, I'm wondering if they're reaching the full HP that the electric motors are capable of, even with power coming from both the batteries and the generator.
 

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Discussion Starter · #6 ·
I think the software played a part in the HP reduction because it is regulating the RPM's of the ICE. Part of the solution to the noise problem was apparently to tweak how the ICE revs, so apparently they reduced the RPM's to reduce noise, thus reducing power.

-Brian[hr]
*** UPDATE ***

I just got this email directly from Fisker:

I am writing you again to correct something that I sent you earlier. I was told that the torque would not change, but that is incorrect. It will change, from 981 to 959. I am sorry about the confusion.


So, a 22 bhp reduction in torque.

-Brian
 

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Mycroft said:
My understanding is that the batteries aren't powerful enough to drive the electric motors at full power on their own (at the motor's full HP), and that's why the engine has to be running in Sport mode. Now that they've had to reduce the power of the engine, I'm wondering if they're reaching the full HP that the electric motors are capable of, even with power coming from both the batteries and the generator.
At one time, the numbers were (all of these are from memory): 300 kW (ie 400 hp) of electric motor draw maximum; 150 kW draw from batteries; 175 kW draw from generator. All of those may have been approximate in the first place, and/or erroneous, and/or changed :D as they were all drawn from various tidbits released over time. Still, if they're close, that means there was enough room to drop the generator output by 25 kW and still drive the electric motors at full torque.

Of course, there was also mention somewhere that 125 mph was top continuous speed, not absolute top speed, and that there was a higher but temporary passing speed. So perhaps the 300 kW output is a temporary maximum in the first place, or perhaps there is/was a 325 kW temporary maximum.
 

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ct-fiskerbuzz said:
Of course, there was also mention somewhere that 125 mph was top continuous speed, not absolute top speed, and that there was a higher but temporary passing speed. So perhaps the 300 kW output is a temporary maximum in the first place, or perhaps there is/was a 325 kW temporary maximum.
I recall something like 140 MPH as the absolute top speed that could be sustained for short periods of time.

Maybe Fisker could add a software switch that would let us select the higher power output from the engine even if it makes it more noisy.

-- Fab.
 

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Discussion Starter · #9 ·
If I remember correctly the car is electronically limited to 125MPH because the batteries overheat at higher speeds.

-Brian
 

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Fabulist said:
ct-fiskerbuzz said:
Of course, there was also mention somewhere that 125 mph was top continuous speed, not absolute top speed, and that there was a higher but temporary passing speed. So perhaps the 300 kW output is a temporary maximum in the first place, or perhaps there is/was a 325 kW temporary maximum.
I recall something like 140 MPH as the absolute top speed that could be sustained for short periods of time.

Maybe Fisker could add a software switch that would let us select the higher power output from the engine even if it makes it more noisy.

-- Fab.
I am all in favor of this option, if it is what is in fact causing the drop in acceleration. I, for one, would much rather have more noise and get to 60 in 5.9 versus 6.3.
 

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Thebreadman said:
Fabulist said:
Maybe Fisker could add a software switch that would let us select the higher power output from the engine even if it makes it more noisy.
I am all in favor of this option, if it is what is in fact causing the drop in acceleration. I, for one, would much rather have more noise and get to 60 in 5.9 versus 6.3.
It sure would be nice, yes.

Software is wonderful this way, in that you can do this sort of thing almost cost-free. Except it never turns out to be as "cheap" as it looks ... sure, it's just a few lines of code (or data entries in tables, or whatever—it all depends on the overall system). But then it gets complicated when something breaks, because now you have to know which configuration(s) were active when, and so on.

So ... if they'll do it, great. If they'll let end users do it without formal support but without voiding warranties, that's ... not as great, but understandable. I just hope that (assuming that this is a software item in the first place) they allow us to do it at all....

(This is similar to my take on the "Tron sound" "ringtones" issue. Fisker themselves don't need to provide "ringtones", they just need to let third party tweaking happen without warranty-voiding. Not a necessity, but sure would be nice.)
 

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brian said:
I just got this email directly from Fisker:

I am writing you again to correct something that I sent you earlier. I was told that the torque would not change, but that is incorrect. It will change, from 981 to 959. I am sorry about the confusion.


So, a 22 bhp reduction in torque.

-Brian
Sorry.. what units? (and measured where?)
Certainly not brake horsepower.

Has Fisker ever released Torque and HP curves like the ones Tesla has?

Model S:


Roadster:



[hr]
Fabulist said:
Maybe Fisker could add a software switch that would let us select the higher power output from the engine even if it makes it more noisy.
Possible, but it might not be allowed by CARB due to emissions.
 

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i saw this You tube post...is this what Karma owners are really experiencing? I am waiting for my delivery:
http://www.youtube.com/watch?v=gKmKGMP9uKw&feature=related
 

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doc said:
i saw this You tube post...is this what Karma owners are really experiencing? I am waiting for my delivery:
http://www.youtube.com/watch?v=gKmKGMP9uKw&feature=related
No, this is not exemplary of what Karma-drivers are experiencing. It happened to someone - I think Brian - whose car was not functioning properly at that time (problems that have since been resolved, I believe)
 

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Dutch said:
No, this is not exemplary of what Karma-drivers are experiencing. It happened to someone - I think Brian - whose car was not functioning properly at that time (problems that have since been resolved, I believe)
It might be a good idea to delete the video from YouTube, since it is not representative of what happens in Sport mode, with or without battery range at 0 miles.
 

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This is not at all representative. It's slower when the battery is fully depleted, but nowhere near this slow.
 

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dennis said:
Dutch said:
No, this is not exemplary of what Karma-drivers are experiencing. It happened to someone - I think Brian - whose car was not functioning properly at that time (problems that have since been resolved, I believe)
It might be a good idea to delete the video from YouTube, since it is not representative of what happens in Sport mode, with or without battery range at 0 miles.
I dislike the idea of deleting it entirely, but perhaps Brian could go annotate it with: "if yours does this, it's not working right, and you should go get it fixed."
 

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doug said:
Has Fisker ever released Torque and HP curves like the ones Tesla has?
No curves have been released. That said, any Karma owner can have these graphs produced by a reputable dyno testing shop, like GMG:

http://www.gmgracing.com/dyno.shtml

 

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Discussion Starter · #19 ·
ct-fiskerbuzz said:
I dislike the idea of deleting it entirely, but perhaps Brian could go annotate it with: "if yours does this, it's not working right, and you should go get it fixed."
Yeah, the car has never done that behavior again, but then again I've made sure to never let the battery run out if the check engine light is on. The video on YouTube is now private, so it doesn't show up anywhere but here where the direct links are.

-Brian
 

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Brian,

You haven't changed your avatar in a while. Are you still feeling like a Beta, or perhaps you're ready to upgrade to "Release Candiate' or perhaps even a proud "Fisker Owner (s Club)"

Brent
 
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