Chevy To Make Spark E.V

130 HP With 400 lb-ft torque,

400 lbs torque in this ?





That's more torque than a 3.0 L TDI Audi A4 , in the size of the spark :eek:

The Leaf is a lot of fun when you hit the throttle, I can only imaging having 400 lbs of torque instantly

colm_mcm

Have you seen the Zap Xebra?

colm_mcm

colm_mcm wrote: »

Have you seen the Zap Xebra?

LOL just looked it up why ?

colm_mcm

Seems to be loosely based on a Chinese car that was famously a rip of the Chevrolet matiz

CiniO

Deleted User wrote: »

130 HP With 400 lb-ft torque,

400 lbs torque in this ?



That's more torque than a 3.0 L TDI Audi A4 , in the size of the spark :eek:

The Leaf is a lot of fun when you hit the throttle, I can only imaging having 400 lbs of torque instantly

Amount of torque on the engine output tells absolutely nothing unless you know the transmission rates.

130 HP tells much more about the engine.
Assuming it will have this 400 lb*ft torque available through most of it's rev's range (like most electric motors), then it means that it's max revs will be very low, and therefore transmission ratio will have to be insanely high.

CiniO

CiniO wrote: »

Amount of torque on the engine output tells absolutely nothing unless you know the transmission rates.

130 HP tells much more about the engine.
Assuming it will have this 400 lb*ft torque available through most of it's rev's range (like most electric motors), then it means that it's max revs will be very low, and therefore transmission ratio will have to be insanely high.

Well it doesn't exactly have a transmission, just a reducer gear like most electric cars.

I'd imagine the revs will be quiet high, hence the need for a reducer gear because electric motors are more efficient at high rpm.

You see they have 100 kw of power to play with and with a limit of 80 or so mph means they can have most of that power as torque.

It should be a very fun car indeed.

colm_mcm

colm_mcm wrote: »

Seems to be loosely based on a Chinese car that was famously a rip of the Chevrolet matiz

Could be a rip off al right ?

I just saw a petrol spark today funny enough I never noticed them before .

colm_mcm

the chinese rip off is called the Chery QQ


You can even put the doors from the chery on the Chevy and they'll fit.

CiniO

Deleted User wrote: »

Well it doesn't exactly have a transmission, just a reducer gear like most electric cars.

I'd imagine the revs will be quiet high, hence the need for a reducer gear because electric motors are more efficient at high rpm.

If this engine really provided 400 lb*ft say at 5000rpm then it would have 380 HP.
You said yourself it has 130BHP, so the highest RPM is can go to with such torque (400 lb*ft) would be 1700rpm.

If this engine provides 400 lb*ft torque above 1700rpm, then it must produce more than 130 HP.

It's that simple.

You see they have 100 kw of power to play with and with a limit of 80 or so mph means they can have most of that power as torque.

I don't get what you mean by that. How can you have power as torque.
Those are two different measures for measuring two different things.

MuppetCheck

It still looks like something my dog would leave behind in the garden. Cheap to run is all well and good but looking at that thing on a daily basis is enough of an incentive to keep buying fuel for almost anything else.

CiniO

CiniO wrote: »

If this engine really provided 400 lb*ft say at 5000rpm then it would have 380 HP.
You said yourself it has 130BHP, so the highest RPM is can go to with such torque (400 lb*ft) would be 1700rpm.

If this engine provides 400 lb*ft torque above 1700rpm, then it must produce more than 130 HP.

It's that simple.

Electric car motors usually spin much faster. Maybe 15,000 rpm. Hence the need for the reducer gear.

CiniO wrote: »

I don't get what you mean by that. How can you have power as torque.
Those are two different measures for measuring two different things.

Horse power is a unit of power in KW so you can have a car with a crap load of torque or a higher top speed, with normal cars it's more complicated where you have a gearbox.

With electrics it's more simple, higher voltage means higher top speed and more current means torque and greater acceleration.

So 130 hp in an electric is completely different to that of and ICE.

So 97 kw of power is still 97 kw of power it never changes, just how you want that power ,speed or acceleration or bit of both.

MuppetCheck

MuppetCheck wrote: »

It still looks like something my dog would leave behind in the garden. Cheap to run is all well and good but looking at that thing on a daily basis is enough of an incentive to keep buying fuel for almost anything else.

Yeah it's ugly as hell but I bet you would have so much fun driving it that you couldn't care less.

Get a drive in a leaf and imaging twice the shove when you plant the throttle and you'll know what I'm talking about.

CiniO

Deleted User wrote: »

Electric car motors usually spin much faster. Maybe 15,000 rpm. Hence the need for the reducer gear.

As I said it's impossible that this motor will spin at 15,000 rpm with 400lb*ft torque and deveop only 130BHP.
If it spun that fast still keeping 400 lb*ft torque, then it's power would be 1142 HP.

Horse power is a unit of power in KW so you can have a car with a crap load of torque or a higher top speed, with normal cars it's more complicated where you have a gearbox.

With electrics it's more simple, higher voltage means higher top speed and more current means torque and greater acceleration.

So 130 hp in an electric is completely different to that of and ICE.

So 97 kw of power is still 97 kw of power it never changes, just how you want that power ,speed or acceleration or bit of both.

Sorry man, that all what you've written above proves you have very little knowledge about what actually power and torque is.

MuppetCheck

Deleted User wrote: »

Yeah it's ugly as hell but I bet you would have so much fun driving it that you couldn't care less.

Get a drive in a leaf and imaging twice the shove when you plant the throttle and you'll know what I'm talking about.

Fun isn't just about acceleration.

colm_mcm

MuppetCheck wrote: »

Fun isn't just about acceleration.

It is on an American car though.

CiniO

CiniO wrote: »

As I said it's impossible that this motor will spin at 15,000 rpm with 400lb*ft torque and deveop only 130BHP.
If it spun that fast still keeping 400 lb*ft torque, then it's power would be 1142 HP.


Sorry man, that all what you've written above proves you have very little knowledge about what actually power and torque is.

An electric motors torque is a result of current not rpm.

MuppetCheck

colm_mcm wrote: »

It is on an American car though.

There's nothing American about that Korean heap.

MuppetCheck

MuppetCheck wrote: »

There's nothing American about that Korean heap.

Weren't they Daewoo ?

MuppetCheck

MuppetCheck wrote: »

Fun isn't just about acceleration.

True, but I bet you would be impressed all the same.

ManMade

From the OP it looks a lot like a corsa.

Edit: just remember they are both GM

MuppetCheck

Deleted User wrote: »

True, but I bet you would be impressed all the same.

But there's more to a car than that. Hence the reason hybrids and Evs up to now have missed the mark for me at least. They never seem to be in something that I'd actually want to/could buy.

MuppetCheck

MuppetCheck wrote: »

But there's more to a car than that. Hence the reason hybrids and Evs up to now have missed the mark for me at least. They never seem to be in something that I'd actually want to/could buy.

Ah yeah know what ye mean, but the Prius for me, while not the most exciting and I miss my old A4, the Prius is a great car and deserves recognition as being a great reliable car. It doesn't pretend to be anything other than a workhorse and a very practical one at that.

But seriously, go take a drive in the Leaf and tell me you are not impressed.

ManMade

ManMade wrote: »

From the OP it looks a lot like a corsa.

Edit: just remember they are both GM

Hmmmm I thing I actually see some resemblance, but the Corsa is at least better looking.

colm_mcm

That shape has been out a good while.
Looks alright in the flesh for a small car.

CiniO

Deleted User wrote: »

An electric motors torque is a result of current not rpm.

Torque in rotary movement is equivalent to force in straight line movement.

Yes - in electric motor rotary movement of the crankshaft is a result of electromagnetic force produced by electricity.
In combustion engine rotary movement of crankshaft is a result of movement of pistons which move due to fuel combustion.

Torque is just a measure how strong this rotary movement of crankshaft is.
RPM is a measure of how fast this rotary movement is.

Eventually this movement is transmitted (through transmission) to the driving wheels.
And now depending on transmission ratio, torque and rpm on the driving wheels change. If RPM on driving wheels will be higher than on crankshaft, then torque will be smaller, and opposite - if RPM is lower, then torque will be bigger.
RPM on driving wheels can you how fast the car is going.
Torque on driving wheels can shows how fast the car can accelerate.

Transmission ratio, as you said depends on the car. In standard petrol car there are usually 5 or 6 gears with various ratios. In electric vehicles there might be CVT with infinite amout of ratios or only one ratio.

But no matter what, RPM and torque on the engine crankshaft tell nothing about car speed or power.

Hope this gives you some idea what's it all about.

MuppetCheck

Deleted User wrote: »

But seriously, go take a drive in the Leaf and tell me you are not impressed.

Day off tomorrow so might well do it for the craic.

CiniO

CiniO wrote: »

Torque in rotary movement is equivalent to force in straight line movement.

Yes - in electric motor rotary movement of the crankshaft is a result of electromagnetic force produced by electricity.
In combustion engine rotary movement of crankshaft is a result of movement of pistons which move due to fuel combustion.

Torque is just a measure how strong this rotary movement of crankshaft is.
RPM is a measure of how fast this rotary movement is.

Eventually this movement is transmitted (through transmission) to the driving wheels.
And now depending on transmission ratio, torque and rpm on the driving wheels change. If RPM on driving wheels will be higher than on crankshaft, then torque will be smaller, and opposite - if RPM is lower, then torque will be bigger.
RPM on driving wheels can you how fast the car is going.
Torque on driving wheels can shows how fast the car can accelerate.

Transmission ratio, as you said depends on the car. In standard petrol car there are usually 5 or 6 gears with various ratios. In electric vehicles there might be CVT with infinite amout of ratios or only one ratio.

But no matter what, RPM and torque on the engine crankshaft tell nothing about car speed or power.

Hope this gives you some idea what's it all about.

But we're talking electric drive and that's completely different form an ice.

With the electric motor in an e.v it spins fast for efficiency because of heat at low rpm with high current, so the need to spin the motor fast, so the reducer gear slows down the rpm and increases torque.

An electric motor produces max power at 0 rpm and a petrol engine at high rpm so comparing the 2 is not really useful.

For more acceleration in an e.v you always need to increase the current and the rpm for speed you increase the voltage.

An engine has to be spinning to create torque, and electric motor produces all it's torque from 0 rpm.

MuppetCheck

MuppetCheck wrote: »

Day off tomorrow so might well do it for the craic.

yeah do, you won't regret it !

MuppetCheck

Deleted User wrote: »

yeah do, you won't regret it !

We'll see. Need to find time between the to-do list that has been handed to me by herself first...

CiniO

Deleted User wrote: »

But we're talking electric drive and that's completely different form an ice.

With the electric motor in an e.v it spins fast for efficiency because of heat at low rpm with high current, so the need to spin the motor fast, so the reducer gear slows down the rpm and increases torque.

Where is the torque and RPM you stated calculated?
On the exit from the electric motor, or after going through this reducing gear?
Because on all fuel and diesel engines it's calculated on the engine, so I assumed, it's the same with electric motors.

An electric motor produces max power at 0 rpm

This again proves you have no clue what you are talking about.
Power of any engine at 0rpm will be 0. Nothing will change it.

and a petrol engine at high rpm so comparing the 2 is not really useful.

It is, as what you said above is not correct.
Power is a measure of the rate at which work is performed. At 0 rpm, there is no work performed at all.

For more acceleration in an e.v you always need to increase the current and the rpm for speed you increase the voltage.

Still not sure what you mean by that.
Voltage on batteries in EV is always the same.
There surely is control system which can adjust electric motor speed and cause accelerating.

An engine has to be spinning to create torque, and electric motor produces all it's torque from 0 rpm.

Combustion engine can't work below some RPM (usually around 700 - 800) and indeed its torque varies a lot through rpm range, while in electric motor torque is usually quite stable through all rpm range.
But what is has to do with things we are talking about?

MuppetCheck

MuppetCheck wrote: »

We'll see. Need to find time between the to-do list that has been handed to me by herself first...

Lol.

IF you do get a chance just make sure eco mode is off.

CiniO

CiniO wrote: »

Where is the torque and RPM you stated calculated?
On the exit from the electric motor, or after going through this reducing gear?
Because on all fuel and diesel engines it's calculated on the engine, so I assumed, it's the same with electric motors.

No Idea, I just go by the figures given for the different cars which I'm sure are calculated the same. So the Leaf has 230 or so lbs torque, I would expect the Spark ev with 400 to accelerate with far more force.

CiniO wrote:

This again proves you have no clue what you are talking about.
Power of any engine at 0rpm will be 0. Nothing will change it.

Yes engine, but not electric motors. An engine has to take in air compress it and so on an electric motor doesn't and not only that a motor is 80+ % efficient compared to 25 or so % of an engine, so a 107 hp engine will not have the same power as an electric motor.

CiniO wrote: »

It is, as what you said above is not correct.
Power is a measure of the rate at which work is performed. At 0 rpm, there is no work performed at all.

Yes in an engine, an engine needs to spin at a few thousand rpm to produce enough torque a motor produces it all from 0 rpm.

CiniO wrote: »

Still not sure what you mean by that.
Voltage on batteries in EV is always the same.
There surely is control system which can adjust electric motor speed and cause accelerating.

More voltage means more rpm meaning the motor will spin faster meaning a faster top speed, dumping more current means more torque and it will accelerate faster, SO the final speed is not just determined by voltage alone but by gearing and software. There is a trade off in electrics where the high rpm of the motor is converted to low rpm for better efficiency at slow speeds resulting in a slower top speed. But you can increase the voltage more but would mean a bigger battery.

CiniO wrote: »

Combustion engine can't work below some RPM (usually around 700 - 800) and indeed its torque varies a lot through rpm range, while in electric motor torque is usually quite stable through all rpm range.
But what is has to do with things we are talking about?

Lost you here ? and I'm heading to bed but we can discuss this again tomorrow.

CiniO

Deleted User wrote: »

No Idea, I just go by the figures given for the different cars which I'm sure are calculated the same. So the Leaf has 230 or so lbs torque, I would expect the Spark ev with 400 to accelerate with far more force.

It's the power parameter that you need to look at, not torque.
Leaf AFAIK has 107 HP. Spark will have 130 HP. Assuming they are similar weight, most likely spark will be slightly faster.

Fact that Spark has nearly double the torque doesn't reveal any info without knowing the gear ratios, tyre sizes, etc.
But power in BHP is enough to know approximate performace rate for those cars.

Yes engine, but not electric motors.

I meant both. Sorry.

An engine has to take in air compress it and so on an electric motor doesn't and not only that a motor is 80+ % efficient compared to 25 or so % of an engine, so a 107 hp engine will not have the same power as an electric motor.

It will.
107 HP power is 107 HP power no matter if it's generated by combustion engine or electric motor, or anything else.

Yes in an engine, an engine needs to spin at a few thousand rpm to produce enough torque a motor produces it all from 0 rpm.

Torque - yes.
But I think you are forgetting (or are not aware of) that power = torque * revolutions.

So if revolutions are 0, then there can't be any power, no matter if we are talking about electric motor or engine.

More voltage means more rpm meaning the motor will spin faster meaning a faster top speed, dumping more current means more torque and it will accelerate faster, SO the final speed is not just determined by voltage alone but by gearing and software. There is a trade off in electrics where the high rpm of the motor is converted to low rpm for better efficiency at slow speeds resulting in a slower top speed. But you can increase the voltage more but would mean a bigger battery.

You can the same get 15,000rpm from 500volts as well as 1.5volts.
It all depends on electric motor.
Anyway - this voltage and currant talk has very little to do with rpm and torque.

Wheres My ForkandKnife

I'd say you two would be popular at parties:D.

However if that chevy farted €20 notes from the exhaust I wouldn't drive it as it's pig ugly.It make the prius look like a hot hatch.

However I am interested in the technology of the ev and the prius.Or at least I was until I read mad lads posts about them.The one on "learning to drive" them would put anyone to sleep.And when you tell a lad with a dpf problem to get a prius it borders on seeking help.

I get the whole fanboy thing about the prius and ev's but you take saving money to a whole new level.Following your logic I feel like hopping in the coffin now, when I think of all the money I'm wasting on food and other neccessities.Sure I won't be able to have a drink of water when the water charges come in:pac:

ARGINITE

CiniO wrote: »

Torque - yes.
But I think you are forgetting (or are not aware of) that power = torque * revolutions.

So if revolutions are 0, then there can't be any power, no matter if we are talking about electric motor or engine.

Ah I think I misread your quote, you are saying power and not torque.

Wheres My ForkandKnife

Wheres My ForkandKnife wrote: »

I'd say you two would be popular at parties:D.

However if that chevy farted €20 notes from the exhaust I wouldn't drive it as it's pig ugly.It make the prius look like a hot hatch.

However I am interested in the technology of the ev and the prius.Or at least I was until I read mad lads posts about them.The one on "learning to drive" them would put anyone to sleep.And when you tell a lad with a dpf problem to get a prius it borders on seeking help.

I get the whole fanboy thing about the prius and ev's but you take saving money to a whole new level.Following your logic I feel like hopping in the coffin now, when I think of all the money I'm wasting on food and other neccessities.Sure I won't be able to have a drink of water when the water charges come in:pac:

LOL that was funny,

Hey I didn't get the Prius for the (main) reasons of saving money, people seem to misunderstand.

I got the Prius because while looking for another Diesel car to replace the A4 I just couldn't accept buying a diesel with 30-40K more miles on the clock at the time and for 3-4 grand more money. I got a good bargain on the Prius, so it would have been foolish not to have bought it.

I also wanted to own one because I'm a huge technology nut and one reason I enjoy driving the Prius, I also love driving the CRV. Which if they open a LPG station near buy I'll certainly be converting it and will cost similar to run as the Prius on petrol.

Anyway another reason for getting the Prius after was because of it's proven reliability and low enough maintenance.

The fact it's great on petrol for it's size and being automatic was a great benefit, and the lack of the rattle and noise of a diesel.

I can also say that with the miles we clock up the Prius is the most reliable vehicle I've owned by far.

So it's not just down to saving money on fuel.

CiniO

CiniO wrote: »

It's the power parameter that you need to look at, not torque.
Leaf AFAIK has 107 HP. Spark will have 130 HP. Assuming they are similar weight, most likely spark will be slightly faster.

The Spark will only be faster if GM allow it in the controller software.

CiniO wrote: »

Fact that Spark has nearly double the torque doesn't reveal any info without knowing the gear ratios, tyre sizes, etc.
But power in BHP is enough to know approximate performace rate for those cars.

Yes if you compare EV with EV.

Remember that an engine is rated at it's peak output usually high in the rev band, while a motor can produce it at mostly all of it, and also the motor converts more power a lot more efficiently so comparing the 2 isn't the same.

That's why the Leaf with only 107 HP feels very fast off the line.

CiniO wrote: »

107 HP power is 107 HP power no matter if it's generated by combustion engine or electric motor, or anything else.

Yes HP is HP but in the case of the electric car that HP can be used for more acceleration or more top speed, and so the top speed is limited in an e.v by software you can use that HP for more acceleration instead.

CiniO wrote: »

Torque - yes.
But I think you are forgetting (or are not aware of) that power = torque * revolutions.

So if revolutions are 0, then there can't be any power, no matter if we are talking about electric motor or engine.

You could have 0 rpm and no output to the wheels you mean ?

But you can have a stalled motor still producing power but that would be converted to heat very quickly.

That's why the motor in an e.v spins very fast because motors are a lot more efficient at high rpm and the need for the reducer gear because the wheels can't spin that fast. And another reason wheel hub motors are a challenge because output would be proportional to the rpm of the motor and so a very steep hill could cause over heating as the motor wouldn't be efficient at low rpm.

CiniO wrote: »

You can the same get 15,000rpm from 500volts as well as 1.5volts.
It all depends on electric motor.
Anyway - this voltage and currant talk has very little to do with rpm and torque.

Voltage and current do have a lot to do with torque Hp etc.

voltage x current = watts watts =power = torque = hp

Current gives more torque, voltage gives more speed to the motor, it's that simple, Kv of the motor and final gearing do matter also.

colm_mcm

I've seen prices of $25,000 after tax rebate and $32000 before guessed for this car. Isn't this more expensive than a leaf?

Matt Simis

ARGINITE wrote: »

Ah I think I misread your quote, you are saying power and not torque.

It doesnt matter, if the "power" discussed is horsepower for rotating objects and its not even moving, then it has no effective torque or power, it cannot be measured.
EDIT: Thats actually incorrect, you can have torque without movement but you cannot have power. Torque without movement is important for moving a stopped train.. not so much for a car.

horsepower = torque x revolutions per minute / 5,252.

400ft-lbs * 0rpm / 5252 = 0 power.

And, as Cino already said, 400ft-lbs peak torque with 130hp =
RPM formula = HP x 5,252 / torque
Spark EV = 130 x 5252 / 400 = 1706rpm at peak power.

All the relevant formulas wrote:

Horsepower = torque x RPM / 5,252
TORQUE FORMULA= T = HP x 5252 / RPM
RPM formula = HP x 5,252 / torque

Mad_Lad, I dont think its correct to state that there is some "difference" in Electric vs Combustion motors regarding stated power and torque. These are measurements, source of power doesnt matter. A 130hp EV would have the same peak power as a 130hp Passat TDI and with similar gearing and weight, pretty much the same performance. The aforementioned A6 3.0TDI produces 370ft-lbs of torque from 2200 to 3400 RPM (and I think there are faster versions of the engine), which is far more "power" than 400ft-lbs at 1700rpm (peak).

Its also not correct to state that Electric motors "go to 15000rpm" and have the same torque from near 0rpm, they dont on either account, they loose torque as RPM increases and they mostly do not rev anywhere near 15,000RPM in EV applications. There is also a significant difference between DC and AC motors, which in its own world is like comparing the merits of Petrol vs Diesel.


DC Motor for EVs:


AC Motor for EVs:

colm_mcm

colm_mcm wrote: »

I've seen prices of $25,000 after tax rebate and $32000 before guessed for this car. Isn't this more expensive than a leaf?

Probably make it around 25,500 Euros after Government rebate of 5,000 then you stick on a nice profitable 23% VAT, though that doesn't include import taxes or import duties ?

maybe it will be made in Europe ?

The Leaf currently cost €27,500 but they have cheaper options for the updated version along with battery rental options for the first time.

The Cheapest trim leaf will be available in the U.K for €18,750 without battery or rental starts at around 75 pounds or so a month up to 129 Pounds a month for 15,500 miles a year.

Someone on the Leaf UK forum stated that with the excess mileage charge it would actually work out a lot cheaper to rent at a lower package than you need and pay the excess.

You can also buy the battery.

Interestingly enough, if you buy the car with the battery it adds 5,000 pounds, so does that mean the battery costs 5,000 pounds ? if so that is a huge drop in the last 2 years alone.

So probably cost 2,000 for a new one by the time you need a new battery in 8-10 years.

If you fast charge all the time then you'd be better to lease, though they do state that fast charging multiple times a day every day will degrade the battery quicker and they might not cover that.

I don't think fast charging once a day for 10 mins or so would have a bad effect.

ei9go

They think in the US that this is what they call a "compliance car" and will not be built in any volume and will probably be only available in about 12 states who have California type laws.

ei9go

ei9go wrote: »

They think in the US that this is what they call a "compliance car" and will not be built in any volume and will probably be only available in about 12 states who have California type laws.

That was the initial plan, they are going to mass produce it, it comes to Europe next year.

They are also going to make a 200 mile range spark and offer the two and see what people actually buy.

Sesshoumaru

The official website say 0 to 60 mph in less than 8 seconds.

http://www.chevrolet.com/spark-ev-electric-vehicle.html#technology_section

Spark EV features an innovative electric propulsion system drive unit paired with the lithium-ion battery. This mini car has big bite and boasts instant torque. The connection is direct: head, right foot, power, pavement. Without the traditional transmission, torque has nowhere to go except to the tires and road. This helps explain why Spark EV feels so powerful and exhilarating while also achieving 0 to 60 mph in under eight seconds. Tuned specifically for its electric propulsion system, Spark EV puts power in all the right places at the moment it’s needed for a sporty and responsive ride. And Spark EV features a turning radius of 32.6 feet, which beats out the Mini Cooper, so parallel parking in the city is seamless and simple.

I don't know what else you could compare it to, but in comparison to a Mini Cooper, it is faster to 60mph. 10.4s is quite slow for the Mini Cooper Automatic.

http://www.mini.co.uk/model-range/hatch/mini-cooper/information/



It's no Mercedes SLS AMG E Drive, but it looks like it could be fun little car to drive

Big Nasty

colm_mcm wrote: »

the chinese rip off is called the Chery QQ


You can even put the doors from the chery on the Chevy and they'll fit.

That's just the way the Chinese pronounce Chevy silly! :eek:

Matt Simis

Matt Simis wrote: »

It doesnt matter, if the "power" discussed is horsepower for rotating objects and its not even moving, then it has no effective torque or power, it cannot be measured.


400ft-lbs * 0rpm / 5252 = 0 power.

And, as Cino already said, 400ft-lbs peak torque with 130hp =
RPM formula = HP x 5,252 / torque
Spark EV = 130 x 5252 / 400 = 1706rpm at peak power.



Mad_Lad, I dont think its correct to state that there is some "difference" in Electric vs Combustion motors regarding stated power and torque. These are measurements, source of power doesnt matter. A 130hp EV would have the same peak power as a 130hp Passat TDI and with similar gearing and weight, pretty much the same performance. The aforementioned A6 3.0TDI produces 370ft-lbs of torque from 2200 to 3400 RPM (and I think there are faster versions of the engine), which is far more "power" than 400ft-lbs at 1700rpm (peak).

Its also not correct to state that Electric motors "go to 15000rpm" and have the same torque from near 0rpm, they dont on either account, they loose torque as RPM increases and they mostly do not rev anywhere near 15,000RPM in EV applications. There is also a significant difference between DC and AC motors, which in its own world is like comparing the merits of Petrol vs Diesel.


DC Motor for EVs:


AC Motor for EVs:

I think were getting confused ? I think we're all thinking about different things ?

For an ac permanent magnet motor such as the Leaf, torque is a function of current and rpm voltage.

SO turn up the amps and you can get 400 lbs of torque without needing to increase rpm, you also increase the total HP out and watts consumed.

Matt Simis

Deleted User wrote: »

I think were getting confused ? I think we're all thinking about different things ?

For an ac permanent magnet motor such as the Leaf, torque is a function of current and rpm voltage.

SO turn up the amps and you can get 400 lbs of torque without needing to increase rpm, you also increase the total HP out and watts consumed.

Well certainly there is some confusion somewhere!
What we are stating is it doesnt matter how the power was developed (ICE, EV, Wind), power and torque are measurements, to compare disparate things.. that was infact the whole reason Horsepower was invented, to compare "powered" mills to horse drawn mills.

It doesnt/shouldnt matter that a DC motor varies torque from Volts or an AC from Frequency+Volts or an ICE from increased fuel injection/rpm or human from muscle flex etc.


I'm actually a fan of DIY EVs, this is one of the sites I read:
http://www.electric-cars-are-for-girls.com/electric-car-motor.html

Torque and Electric Car Motor Poles
Question: So what's torque got to do with it? Is that a constant, related to the type/size of motor, and moved to the right or left on the graph by the number of poles? I've never understood the poles bit very well. More poles means more low-end torque, less high-end torque? Is there a limit to the number of poles a motor can have?

Answer: Most AC electric car motors are 4 or 6 pole. The more poles, the slower the motor will turn. If both motors have the same horsepower, the 6 pole motor will have more torque and less speed. HP = speed * torque.


Motor torque is related to "slip". Slip is the difference between actual electric car motor speed and commanded motor speed. For example a DC car at a stop can generate lots of torque because 100 volts will produce 2000 rpm of slip. Once you achieve 1900rpm, the torque is limited because now you can only produce 100rpm of slip. With an AC electric car motor, the slip is not limited by voltage, it is limited by frequency, which is basically unlimited. So the motor can produce torque even at high rpms. The constant power nature of the AC electric car motor makes it feasible to drive 0-75mph in only one gear.
Picture a car with a big coil spring on the rear bumper. If you want to accelerate the car slowly, you would push on the spring with slight force, and this would compress the spring slightly "small amount of slip". If you want to accelerate quickly, you would command a large "slip", basically compressing the spring a lot.

DC Motors spin a certain rpm per volt. If 1 volt = 20 rpm, 2 volts will =40 rpm, and 200v will = 8000rpm.

AC motors will spin a certain rpm per cycle. If 1 cycle/second = 20rpm, 60 cycles/second will = 1200rpm. The motor controller can command any frequency it wants to the motor, and of course you need enough voltage and current to produce torque.
...for a DC motor, voltage will limit the max speed of the motor. Unless the motor has a separately wired field, this is true.

The concept of "slip" in the electric motor world is largely analogous to higher torque/acceleration at crank vs wheels in a regular car. I think..

Matt Simis

Matt Simis wrote: »

Well certainly there is some confusion somewhere!
What we are stating is it doesnt matter how the power was developed (ICE, EV, Wind), power and torque are measurements, to compare disparate things.. that was infact the whole reason Horsepower was invented, to compare "powered" mills to horse drawn mills.

It doesnt/shouldnt matter that a DC motor varies torque from Volts or an AC from Frequency+Volts or an ICE from increased fuel injection/rpm or human from muscle flex etc.


I'm actually a fan of DIY EVs, this is one of the sites I read:
http://www.electric-cars-are-for-girls.com/electric-car-motor.html



The concept of "slip" in the electric motor world is largely analogous to higher torque/acceleration at crank vs wheels in a regular car. I think..

Good Website, thanks.

Yes polls will effect torque also motor winding and current.