Fisker Karma

[AnOutsider]

So it really appears like the Karma is a not-so-efficient hybrid performance vehicle without much interior or cargo space. One has to wonder why the government loaned more money to Fisker than was loaned to Tesla despite the fact that the Roadster had proved well in advance that Tesla is capable of producing an efficient EV. I do think the Karma is extremely beautiful and I'm sure there is a market for it, but it's a shame that it doesn't seem like it will end up saving much energy. It's really too bad they can't just take the engine out of the car and replace it with extra batteries the same weight or less than the engine. They'd have a real EV then.... Maybe somebody can do an aftermarket conversion

A Coachbuild based on an actual Fisker base car? The irony!

 

[Dragon]

At the Geneve Automobil Salon, March 2011.

 

[doug]

2011-Car Magazine (April)

In Stealth, the engine does not come on unless the batteries are low on juice. When they are fully charged and you are driving down a hill in regen mode, the surplus energy has nowhere to go so it turns the idle engine, albeit at very low rpm.

Wait, what? Are they saying that the engine has to come on so that they have engine breaking? Then the generator turns into a motor which then turns the engine?

 

[doug]

REEV, then EREV, now EVER; I still call it a PHEV.

 

[PaulM]

Wait, what? Are they saying that the engine has to come on so that they have engine breaking? Then the generator turns into a motor which then turns the engine?

No, I think what they mean is that the electricity generated (in regen mode with full batteries) is sent to the generator attached to the engine. The generator is thus now running like an electric motor turning over the engine. No fuel is being consumed but since the throttle is closed, it acts as an engine brake.

 

[doug]

No, I think what they mean is that the electricity generated (in regen mode with full batteries) is sent to the generator attached to the engine. The generator is thus now running like an electric motor turning over the engine. No fuel is being consumed but since the throttle is closed, it acts as an engine brake.

Doesn't the engine at least have to be running at idle for that?

 

[TEG]

Doesn't the engine at least have to be running at idle for that?

I think you could use an engine not producing spark with no fuel just for engine braking.
As long as it had a mechanical oil pump to keep the lubrication flowing.

 

[PaulM]

Doesn't the engine at least have to be running at idle for that?

No, many modern engines cut the fuel going to the engine when coasting. My TDI does this so when I'm slowing to a stop, killing the ignition makes absolutely no difference. As for lubrication, most oil pumps are mechanically linked to the crankshaft so as long as the engine is turning, so does the oil pump. Even if the oil pump was electrically driven (doubt it), all they have to do is make sure it is running.

 

[ljbad4life]

Has it been explained yet how the Karma is going to deal with stale gas and engine maintenance issues?. My best guess is it will be like the Chevy Volt, every couple of weeks the ICE will have to turn on to lubricate and every couple of months the ICE will have to burn the tank of gas to prevent it from going stale.

 

[AnOutsider]

Surprised no one posted this:

Fisker Begins Karma Production in Finland

Start-up electric-vehicle maker Fisker Automotive confirms Job One today of its Karma sports sedan at Valmet Automotive in Finland, saying the plan is to ramp up slowly to avoid any hiccups on the $100,000 EV.

“The cars coming down the line, as from today, are full-production specification and build, but at the moment are very limited in quantity as we ensure full quality,” says Roger Ormisher, a spokesman for the Irvine, CA-based auto maker.

 

[zack]

Wow, that article refers to it as an EV as well. Amazing!

 

[benji4]

Wow, that article refers to it as an EV as well. Amazing!

In that very short piece, a range-extended EV, a plug-in EV, and even just plain a "EV". Nobody is sure what it should be called really. I like to think of it as a performance-enhanced ICE vehicle since that's what the motor is (mainly) for in the Karma.

 

[doug]

First Fisker Karma Plug-In Rolls Off the Line | Autopia | Wired.com

 

[zack]

Wow, such staggering stats, with such limited performance. "403 horsepower and 901 foot-pounds of torque"

 

[doug]

Delaware business: Analysts doubting Fisker's projections

 

[zack]

Not exactly a ringing endorsement. At least they referred to it as an "other" rather than EV.

 

[strider]

Wow, such staggering stats, with such limited performance. "403 horsepower and 901 foot-pounds of torque"

I agree. The numbers just don't jive for me. How can 0-60 be so piss-poor (5.9) w/ so much torque? Model S is expected to have ~295 lb-ft and a similar 0-60 time. Something is fishy - either the torque quoted is way too high or the car has serious problems getting that power to the ground.

 

[ljbad4life]

I agree. The numbers just don't jive for me. How can 0-60 be so piss-poor (5.9) w/ so much torque? Model S is expected to have ~295 lb-ft and a similar 0-60 time. Something is fishy - either the torque quoted is way too high or the car has serious problems getting that power to the ground.

I'm thinking that there are 4 options:

1) 403hp is what the motor is capable of but it is limited because of heat dissipation issues

2) 403 hp motor, but limited because the battery output is not high enough for the full 403hp

3) The Fisker Karma is a porker 5k lbs is a lot of weight (some rumblings that it will be 5,500 lbs)

4) all or any combination of the above

what do you guys & gals think?

 

[stopcrazypp]

#1 (overheating motor) I don't think is an issue given the power is spread over two motors.

#2 (batteries) is definitely an issue. The Karma's batteries can only output 160kW (216hp), which is why the 0-60 is only 7.9 and top speed 95mph in electric "Stealth" mode (same as the much cheaper Volt).
http://www.automobilemag.com/green/reviews/1102_2012_fisker_karma/electric_vehicle.html

#3 (weight) I suspect is the biggest issue. Acceleration depends heavily on weight. The base V6 Panamera ($75k) gets the same 0-60 with only 300hp but weighs much less (~3900lbs). If it is truly outputting 403hp, then the weight probably is significantly over 5000lbs given my analysis below.

I found 0-60 for other cars with ~400hp in the large and heavy category, but all of them weighed less than 5000lbs and performed better, the closer one is the S550:
5.4 - S550 ($92k) ~4500lbs (382hp)
5.2 - V8 Panamera ($90k) ~4000lbs.
5.1 - 750i ($82k) ~4600lbs
5.1 - Quattroporte ($120k) ~4400lbs

For the hybrids, it seems the 600h L is the closest match (more than 5000lbs, not quite 400hp, but it still gets a significantly better suggested 0-60):
7.1 - S400 ($89k) ~4400lbs (275hp)
5.5 - 600h L ($111k) ~5200lbs (389hp)
4.7 - 750i ActiveHybrid ($102k) ~4800lbs (455hp)

 

[strider]

Forget horsepower - 0-60 is all about torque and the Fisker is in Veyron territory (922 ft-lbs) which has a 0-60 of 2.5 seconds. Yes, the Veyron is ~25% lighter but even so w/ that much torque the Fisker should AT LEAST be in the 4's. So do you think they're quoting max torque of the motors but the Fisker PEM/batteries/engine can't supply enough juice to realize all the available power? I think they're making a mistake quoting these numbers - ICE gearheads (magazines, TV shows, etc) will know what 901 ft-lbs is supposed to feel like and they won't get it.