2.0l LNF rev limit 3500rpm

2671 Views 5 Replies 4 Participants Last post by EVer1, Jun 20, 2012

WreckedKarma

Discussion Starter · Jun 19, 2012

So after monitoring the ICE engine on the Fisker with the ODB tool the GM LNF motor is rev limited to 3500rpm????!!!?!?!?!

are you kidding me fisker? the motor is stock tuned from GM to rev to 5300 rpm..

Horsepower (hp @ rpm) 260 @ 5,300
Torque (lb-ft @ rpm) 260 @ 2,000

does anyone know what the boost is on the fisker? is it running at the stock 16lbs?

My hopes were to increase the boost to a factory performance boost of 23psi and increase the rev limiter to the factory performance increase to a modest 6,000rpm. the factory performance GMPP upgrade puts the rev limiter to 6500rpm.

Fisker could make a ton of money charging for a perfomance package just like the Tesla offers.. which increases the output of the power inverter making it a super car producing 0-60 times of 4 seconds..

the way I see the fisker is that we can get that 0-60 time down to 4 seconds just by releasing the power that is already there.

The motors in the fisker are two 120 kW motors... Reviewing the power output, the fisker it tops out at 175kW of output but only gives that burst for about 10 seconds.. then drops to 140kW for another 4 seconds.. then to 100kW for another 6 seconds.. by the time The car is reaching a good speed of about 110mph the kW output to the motors is reaching 80kW.

So I am working with a HPtuner and maybe the fisker software is encrypted?
The software can read the live data output from the motor but it is unable to read the whole software package.. Cannot read the VIN number with VCM Editor and VCM Editor errors out on the read.

Are we maxing out the inverter? can this inverter be upgraded? can I run dual Inverters to distribute 120kW to each motor?

Can someone post pictures of the Inverters? anyone have any info about the inverter manufacture and specs? I know fisker was originally going with a quantum tech inverter with a price tag reaching $10k but switched to lower cost replacement.. was this a lower rated inverter?

the torque is there on the car.. if the ICE can output more power why limit it... most generators have an optimal rpm range which is 3600 RPM so is that the reason for the rev limiter? if its running at optimal output the generator should be pushing 175kwh at 3500rpm? how do we increase this to 3600rpm? optimal rating for the generator?
(20 kWh/180 kW max discharge) and the generator (175kW)
the battery still gets depleted while the gas motor is online.
the car very rarely outputs 175kW. I understand that fisker has said that the output is limited because it doesn't want to overheat the batteries.. well the car is fine in stealth mode.. but why cant the car be pushed to 200 or 250kW output? the motors can take 260kW.

how does one reprogram the inverter? is it possible to replace the inverter with a higher output inverter?

I love the car but it lacks power... like tim the tool man taylor always says.... more power!

If someone can post pics of the components and input on what the limiting factors are that contribute to the lack of power it would be great. The power delivery from 0-20mph is horrible. with 900lbs of torque I should be able to roast these tires, even with the 22's

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Fabulist

· #2 · Jun 19, 2012

@WC: Many of these questions have been addressed in threads such as this. There are other posts by @Nimsys that addressed similar topics that you may find interesting. I think the Karma's limits were set very conservatively to maximize lifetime and reliability. After some experience with the car in the field, they may find that they can relax some of the limits without degrading the car's long-term reliability significantly.

Alternatively, they can give the driver a "Click here to agree" type screen that tries to absolve Fisker of liability if the relaxed limits damages the car so that you can make the choice between longer life and more power.

IMHO, Jailbreaking the Karma at this stage would be a very bad idea since the underlying software is still evolving and not completely stable yet and tweaking parameters may not be the best idea when they are trying to debug the underlying code. It also suffers from the problem that each time Fisker issues a new release, the jailbreak would be lost and you have to start over again.

As much as I would love to have more off-the-line speed and better acceleration, I would not even consider tweaking the software at this stage while Fisker is still working on it.

Finally, "It has enough power for my wife" sounds sexist and a bit condescending. In my experience, female drivers appreciate more power just as much as male drivers.

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WreckedKarma

Discussion Starter · #3 · Jun 19, 2012

Awesome.. I was looking for those photo's but for some reason every search I tried came up empty.. Its nice to know that there are two inverters... wonder what the limits are of the units..
I see the inverter pictures but its not close enough to see the model numbers..

there is no gender discrimination going on here.. more like gender stereotyping.. My wife does not care about how much power a car has. I would say 98% of women prefer a reliable car vs a loud and fast car. In my experience girls do not like to be stranded on the side of the road. It has been posted many times on this forum that we do not want to have our wives, girlfriends, kids, etc.. drive the car because we don't want to have the car leave them stranded.

so would " its reliable enough for my wife to take the kids to school everyday " sexist to? lets not be so sensitive and just have a good chuckle.

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jrocks

· #4 · Jun 19, 2012

Before I took delivery, a tech had told me that he was at one of the training sessions with a Corporate Engineer and they had a Karma that had different software for testing purposes only and though the battery life wasn't that good, it was clocking 0-60 times BELOW 4 seconds.

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Fabulist

· #5 · Jun 19, 2012

WreckedKarma said:
there is no gender discrimination going on here.. more like gender stereotyping.. My wife does not care about how much power a car has. I would say 98% of women prefer a reliable car vs a loud and fast car. In my experience girls do not like to be stranded on the side of the road. It has been posted many times on this forum that we do not want to have our wives, girlfriends, kids, etc.. drive the car because we don't want to have the car leave them stranded.

Sorry, I think my statement came out a lot harsher than intended. On the rare occasions that my spouse drives the Karma (usually after a dinner where I have had a few glasses of a fine red wine), she has no problem flogging the throttle and zipping the car around in traffic. My only point was that the power question would easily apply to all drivers, regardless of their gender. But enough political correctness; as Jeremy Clarkson famously says when he is test driving a car "powerrrrrrrrr!"

[hr]

jrocks said:
Before I took delivery, a tech had told me that he was at one of the training sessions with a Corporate Engineer and they had a Karma that had different software for testing purposes only and though the battery life wasn't that good, it was clocking 0-60 times BELOW 4 seconds.

I would LOVE to have that option for occasional use. They can even limit it to x number of times/day. But it would be awesome to smoke smug-looking V8 drivers off the line, in almost total silence. I don't mind paying for the additional acceleration with rapidly decreased range, just like you do with a gasoline-powered engine. I just don't want it to damage the battery or reduce its life significantly.

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