"Mr. FiSTer of Team FiST Fetish" (mrfist)
03/23/2018 at 15:08 • Filed to: None
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"Mr. FiSTer of Team FiST Fetish" (mrfist)
03/23/2018 at 15:08 • Filed to: None | 0
| 13 |
Saw this today and thought it was strange, why would an electric car need paddles?
DucST3-Red-1Liter-Standing-By
> Mr. FiSTer of Team FiST Fetish
03/23/2018 at 15:15 |
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I think the lastest Volt has them for regen braking. Maybe something along the same lines?
OpposResidentLexusGuy - USE20, XF20, XU30 and Press Cars
> Mr. FiSTer of Team FiST Fetish
03/23/2018 at 15:17 |
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bhtooefr
> Mr. FiSTer of Team FiST Fetish
03/23/2018 at 15:18 |
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Two reasons.
In this case, because it’s not an electric car, it’s a plug-in hybrid, and it has an 8-speed automatic.
Another case, though, is for regenerative braking, and changing how much of it you get. The Volkswagen EVs use a manual shifter position to increase/decrease regen on the accelerator pedal. The Cadillac ELR, Gen 2 Chevrolet Volt, and IIRC the Chevrolet Bolt use a paddle to engage extra-strong regen.
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Mr. FiSTer of Team FiST Fetish
> bhtooefr
03/23/2018 at 15:26 |
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I feel like I’ve only seen stuff about the battery tech but that makes sense, this thing should even pretty cool.
TheTurbochargedSquirrel
> Mr. FiSTer of Team FiST Fetish
03/23/2018 at 15:31 |
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You can still have a transmission with an electric motor.
Pich, with Z32 now featuring Civic [Si] / No
> Mr. FiSTer of Team FiST Fetish
03/23/2018 at 16:36 |
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gotta switch between AA and AAA
Spanfeller is a twat
> TheTurbochargedSquirrel
03/24/2018 at 09:59 |
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Many formula E teams run transmissions... but many others don’t
it depends on how you want your engine to output at a certain RPM and how it relates to wheel speed, but generally it seems to cause too many mechanical losses to be justified, even tesla tried putting a transmission in the Roadster and they said it wasn’t worth it.
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TheTurbochargedSquirrel
> Spanfeller is a twat
03/24/2018 at 16:39 |
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I engineer electric race cars, I understand the trade-offs made in electric powertrains.
Tesla ditched the 2 speed gearbox in the Roadster because they couldn’t get it to stop breaking.
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Spanfeller is a twat
> TheTurbochargedSquirrel
03/24/2018 at 16:42 |
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Do you think it would be worth it (a gearbox) in thr polestar application?
Yes! It broke... I had forgotten that was the reason.
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TheTurbochargedSquirrel
> Spanfeller is a twat
03/24/2018 at 16:53 |
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Depends on what kind of performance they are targeting and what kind of motor they are using. If they are using a motor that only revs to 6-8k rpm a gearbox would allow them to achieve both fast acceleration and high top speed (Tesla’s motors rev to 14k+, allowing them to achieve a high top speed with short gear ratios). A gearbox also allows them to keep the motor closer to it’s peak efficiency point. With the kind of car Polestar has traditionally built a gearbox would make sense for the increased driver involvement.
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Spanfeller is a twat
> TheTurbochargedSquirrel
03/24/2018 at 17:01 |
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Would being able to keep the motor at its most efficient overcome the mechanical losses of a gearbox?
It would mean the motor could be made to spin a lot slower than a Tesla motor... Not that I understand the benefits of that just yet.
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TheTurbochargedSquirrel
> Spanfeller is a twat
03/24/2018 at 19:17 |
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From a power delivery perspective yes, probably not from an efficiency perspective.
The comparison with a Tesla motor has more to do with gearing than anything. If a Tesla motor can rev to 14k and do both 0-60 in 2s and 150mph, a motor that makes the same torque as a Tesla motor that only revs to 7k would still be able to do 0-60 in 2s but would only be able to run out to about 75mph.
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Spanfeller is a twat
> TheTurbochargedSquirrel
03/24/2018 at 19:57 |
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Well, there must be a benefit for slower engines (even if they probably had to be physically larger to equal torque) then in case of power delivery a 7 speed auto or a CVT would make good sense....