# Tesla Fast off the Line



## rochesterricer (Jan 5, 2011)

Jack is talking out of his ass again. If you want to compare short acceleration distances, then look at 60 foot times. According to Dragtimes, the Model S did a 1.9 60 ft for them. Plenty of ICE cars can beat that in stock trim, such as the C7 Corvette and the Nissan GTR. 

He might have a point if you start from idle, but the transmissions in ICE cars don't require them to start from idle on a drag launch. 

The powerband of an EV is most advantageous during on/off throttle transitions. That is there where the Model S may indeed be hard to beat. 

The Model S is an amazing vehicle on its own merits. It doesn't need to be oversold with fish stories and claims like this.


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## Duncan (Dec 8, 2008)

There is a point here - 
the Roadster was not as fast as a standard Lotus - 
*In the hands of a skilled racing driver
*
If you were not in exactly the correct gear - the Roadster would leave you for dead

So in a really fast IC car if you have launch control and you have set it up,
Or if you have exactly the right revs
You can leave the line as fast as a Tesla

If you have not set up your launch control, or have not got your revs just right

The dam Tesla will eat your lunch

This will also be true in normal driving - The Tesla has that available all the time

You don't have to go through all of the rituals of gear change and rev matching before you can go


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## Karter2 (Nov 17, 2011)

Duncan said:


> There is a point here -
> the Roadster was not as fast as a standard Lotus -
> *In the hands of a skilled racing driver
> *
> ...


 ..until you get to the first corner, or max out on speed,...when the standard car bites back !

But the point was..


> "NO production car on the planet has the instantaneous take off of the Model S. You can beat it in the quarter mile. But no ICE engine car would be able to even come close in the first 500 feet. It’s not even theoretically possible."


 ..Which is utter bollocks !


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## Hollie Maea (Dec 9, 2009)

DavidDymaxion said:


> (soap opera alert, apparently he disagrees with Otmar on some things).


It really is remarkable that every single person* that Jack has interacted with ended up being a scoundrel. Man, talk about bad luck! 


*with the exception of Brian Noto. Maybe he's a robot.


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## DanGT86 (Jan 1, 2011)

The way it sounds to me, he is trying to make the point that the time from the driver input to motor reaction is quicker in a tesla than possible with an ICE. That may be true but it has little or nothing to do with a hypothetical or real world drag race to any practical distance.

That whole statement about it being impossible to beat to 500ft seems like bait for an internet argument. There are also tons of examples in the real world that disprove it. 

There seems to be tons of hype about electic vehicles making maximum torque from zero rpm like that is some magic that is going to make them faster than every other vehicle. Jack's statement sounds like just another version of that talking point.


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## aeroscott (Jan 5, 2008)

He was talking about instantaneous power. Racing is a bad example 
because of the preparation to compensate for a lack of instantaneous power. Hp for hp the ev has less rotating mass and will come out on top, unless it has other disadvantage ,like 1 speed gear box etc.
In real life where you need to get out of the way of something, instantaneous power of the ev may save your life or your wallet on a fast changing yellow light.


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## PStechPaul (May 1, 2012)

I knew someone who claimed that he could beat any car on foot, for the first 50 feet or so. I never saw him demonstrate it, but I do think it is possible. If a runner has a starting block, it is possible to exert more than 1G of acceleration, as must be to be able to jump. I think forces greater than 1G are possible for specially constructed drag racers, but probably not for stock cars. The wiki article I found did not give specific figures, and the math was too much to attempt:
http://en.wikipedia.org/wiki/The_Biomechanics_of_Sprint_Running

This web page shows that a "funny car" can exert 6.5G:
http://www.dirtdrivers.com/articles/columns/article.asp?column=1&article=22

Here is an interesting article that says that the force exerted by a runner on the knee can be 2 to 3 times body weight, or 2-3G. Thus the forward force providing acceleration might be as much as that with a starting block, and probably well over 1G or 9.8 m/sec^2.
http://www.posetech.com/library/cs-05-2001.html


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## Karter2 (Nov 17, 2011)

PStechPaul said:


> Here is an interesting article that says that the force exerted by a runner on the knee can be 2 to 3 times body weight, or 2-3G. Thus the forward force providing acceleration might be as much as that with a starting block, and probably well over 1G or 9.8 m/sec^2.http://www.posetech.com/library/cs-05-2001.html


 Possibly, but that would be a "peak" or "instantaneous" figure not continuous. So the average, effective force is much less.


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## Duncan (Dec 8, 2008)

_"NO production car on the planet has the instantaneous take off of the Model S. You can beat it in the quarter mile. But no ICE engine car would be able to even come close in the first 500 feet. It’s not even theoretically possible."_

You could test this by having a line up of "Fast Cars"
Each one with a driver and a set of lights

If you made the drivers sit with both feet on the floor until the green light then is is very likely that the Tesla driver would be the first to 500ft

If you let them all rev their engines and set up "Launch Control" - then No some of the IC cars would beat the Tesla


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## DanGT86 (Jan 1, 2011)

I just found a chart that showed sprinter Usain Bolt's times to various distances. It says that he takes 2.99 seconds to run the first 75 feet of a race. The tesla is at 60 feet in 1.9 seconds. Its highly unlikely that human runner is beating a sports car to 50 feet. Just for reference, a car like Assault and Battery is already going 60mph in 2 seconds so that better be a fast runner. 

Drag racing is about traction and power to weight ratio. A human just doesnt have the power to weight ratio at most distances beyond a few feet to beat a car. 
Human cyclists can produce 1500 watts in short bursts but weigh 150-200lbs for
.013-.010 hp/lb The tesla is closer to 380whp/4500lbs for .084 hp/lb.

As far as the drag race vs ICE vehicles with drivers' feet on the floor goes, the tesla still gets beat by the many production cars that are just faster. The instant electric motor response time only buys the tesla fractions of a second but it takes about 6-7 seconds for it to get to 500ft. That is just not enough of an advantage to keep the more powerful ICE powered vehicles from overtaking it in that time. The world has lots of 400-600hp cars that are 1000lbs lighter than the tesla.

Its an amazing vehicle but it still has a hp and a weight like any other car.

I spend a lot of time at the dragstrip. Maybe i can find a tesla owner who will volunteer for a test in the name of science. I sure can't afford the tesla or the similar powered ICE vehicle to race against it.


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## aeroscott (Jan 5, 2008)

rotating mass has a multiple effect compared to overall mass. I was thinking 10 to 1 . Just can't remember that number .


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## DanGT86 (Jan 1, 2011)

Rotating mass does factor into acceleration but its already accounted for when looking at a Dyno run or a drag strip time slip. 

If you have two identical motors with the same power output and you put them in the same chassis with the only difference being the efficiency of the driveline, then you would get a different HP number measured at the wheels. If you measure two vehicles at the wheels and get the same number then the rotating mass is already counted and doesn't matter. The road only cares about what the tire is exerting on it. Physics doesn't care how that power got there. 

On that subject, is the rotating mass of the tesla that much less than an ICE car? The 500lb engine in the ICE is not all rotating just he crank with the rods and pistons on it. What does the rotor of the tesla motor weigh?
Also the tesla has a huge 8 or 9:1 gear reduction which might be less efficient than a lower ratio like most ICE cars have. Tesla also has large diameter wheels which put lots of rotating mass far from center killing acceleration. Most nice looking big wheels slow cars down at the track. Other than the lack of transmission I don't know if its driveline mechanics are that much more efficient than the ICE. 

I am not trying to be overly argumentative here but there are published Dyno tested HP numbers for the Tesla and most similar power/weight ICE cars. There are also Drag race time slips out there for both. The time slips show reaction time, 60ft time, 330ft time, 1/8 mile speed and time, as well as other incremental measurements. We have all of the data we need to predict what would happen in a hypothetical race. The existing data as measured in reality disproves the claim of impossible to beat to 500ft. I will concede that penalizing the ice cars by not letting them launch the way they were designed does make for a closer race. But if you take a time slip from something like a zr1 corvette at the drag strip and add .5 seconds to the reaction time or the 60ft time to simulate the rev up time from idle it can still catch or overtake the tesla between 330ft and 660ft. The corvette has the half second made up for by 330ft and is almost a full second quicker at 660ft. 500ft is in between those distances and the corvette is a production car. 

Side note. I would still much rather have the Tesla!


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## aeroscott (Jan 5, 2008)

With the cars having the same weight ,same aero, hp and gearing being equal ( no 1 speed vers 8 speed). the ev will win because of less rotating mass and quicker responding motor. And a less considered thing , the impulses are less in a ev which helps traction. Yamaha uses a special
crankshaft to smooth out the impulses that helps in track times.


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## Karter2 (Nov 17, 2011)

aeroscott said:


> With the cars having the same weight ,same aero, hp and gearing being equal ( no 1 speed vers 8 speed). the ev will win because of less rotating mass and quicker responding motor..


 Yes but that is not realistic !
One of the current advantages of a high power ICE is that it doesnt have to haul around several hundred pounds of battery !


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## Duncan (Dec 8, 2008)

Karter2 said:


> Yes but that is not realistic !
> One of the current advantages of a high power ICE is that it doesnt have to haul around several hundred pounds of battery !


True
But for how long?

The Tesla is a big luxury saloon (6 seats?) - to be comparing it to sports cars and total exotica like the Veyron at many times the price.......

How long before Tesla - or somebody - produces a purpose designed sports car that can blow away the IC cars??


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## Karter2 (Nov 17, 2011)

Duncan said:


> The Tesla is a big luxury saloon (6 seats?) - to be comparing it to sports cars and total exotica like the Veyron at many times the price.......


 Agree, (except its a 5 seater ) 
A better comparison might be an Audi RS7, BMW M6, etc which are very similar in size, (4/5 seats) weight and pricing.
..and both have tested with quicker 0-60 and 1/4 mile times than the Model S 85



Duncan said:


> How long before Tesla - or somebody - produces a purpose designed sports car that can blow away the IC cars??


 Not until someone produces a battery cell that can blow away lithium battery performance..IE double the power and energy density !


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## DanGT86 (Jan 1, 2011)

aeroscott said:


> With the cars having the same weight ,same aero, hp and gearing being equal ( no 1 speed vers 8 speed). the ev will win because of less rotating mass and quicker responding motor.


I would agree that the EV would win if the ice cant use a transmission. Those are some strange terms to race by. That just wouldnt happen and would be a terrible design for an IC vehicle.

Since ice vehicles have a very narrow power band compared to an electric motor they use torque converters and gears to keep the average hp output close to the peak hp throughout the run. The tesla doesnt need the same number of gears since its power band is very flat but that doesnt mean that being single geared makes it more powerful than an Ice with a transmission. It just means that its high motor torque at a wide range of speeds keeps it from needing gears to make power like a normal car. 

If all things are equal but the EV averages higher power during the race then it will in fact win. There are peak numbers and there are avg numbers. The average number or area under the dyno curve makes the car faster in most cases since you have a higher chance of being in the power band at any given moment. But if the ICE using gearing stays close to peak power and its the same average power throughout the race as the ev then its all equal. You have a tie.

If the hp curves on a dyno were exactly the same then rotating mass and gearing are not a factor at all since all of those things were present when power was measured at the wheels on the dyno. That quick responding motor is present on the dyno too so it also shows up on the graph in the form of power.


Its not a magic car its just a really nice fast car. If traction and aero are the same then racing is just a matter of how much weight you are moving and how much power you exert on that weight. Nature doesnt care about the power source.


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## Karter2 (Nov 17, 2011)

DanGT86 said:


> I would agree that the EV would win if the ice cant use a transmission. Those are some strange terms to race by. That just wouldnt happen and would be a terrible design for an IC vehicle........


 Actually, for the 0-60mph sprint test times its not impossible possible for some of those ICE cars to hold 1st gear .. especially some of the high rever's like BMW.. or even just launch in 2nd !
...but the Tesla still gets beat to 60 anyway !


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## DanGT86 (Jan 1, 2011)

Duncan said:


> How long before Tesla - or somebody - produces a purpose designed sports car that can blow away the IC cars??


I feel like tesla already has. That model S does blow away lots of ICE powered cars. Just doesnt beat all of them like the original claim that got me all fired up. The Tesla does hold its own against pretty high end stuff.

Electric drives have lots of advantages in forms of racing with varying speeds and turns. Regen keeps brakes cool and smooth power delivery helps with traction in turns. 

I think electrics will consistently dominate races like pikes peak and perhaps the isle of man tt in the future but without a significant jump in battery tech they probably wont rule drag racing in the near future. Drag racing is all about power density and fossil fuels are hard to beat in that department. I fully support people trying anyway!


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## JRP3 (Mar 7, 2008)

rochesterricer said:


> Jack is talking out of his ass again.


That's his special talent 



Hollie Maea said:


> It really is remarkable that every single person* that Jack has interacted with ended up being a scoundrel. Man, talk about bad luck!
> 
> 
> *with the exception of Brian Noto. Maybe he's a robot.


I think Brian suffers from Stockholm Syndrome. I feel for the guy, seems like a decent individual. Or maybe he is a robot as you say.


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## aeroscott (Jan 5, 2008)

DanGT86 said:


> I would agree that the EV would win if the ice cant use a transmission. Those are some strange terms to race by. That just wouldnt happen and would be a terrible design for an IC vehicle.
> 
> Since ice vehicles have a very narrow power band compared to an electric motor they use torque converters and gears to keep the average hp output close to the peak hp throughout the run. The tesla doesnt need the same number of gears since its power band is very flat but that doesnt mean that being single geared makes it more powerful than an Ice with a transmission. It just means that its high motor torque at a wide range of speeds keeps it from needing gears to make power like a normal car.
> 
> ...


How does the rotating mass show up on a dyno , only a very small part of the mass is effecting untimed hp. Mass relates to time to speed.

Traction can never be the same because of the impulses.

Nothing can beat a 2 motor planetary transmission , like the volt uses.
It just needs to be understood and hacked.


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## aeroscott (Jan 5, 2008)

Karter2 said:


> Yes but that is not realistic !
> One of the current advantages of a high power ICE is that it doesnt have to haul around several hundred pounds of battery !



The only advantage is weight of fuel. Changing all the time.


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## Karter2 (Nov 17, 2011)

For a 0-60 sprint the Ice needs about 1 lb of fuel....
The EV would need about 500lbs of battery for the same test .!!


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## aeroscott (Jan 5, 2008)

1lb. of fuel and 100 years to develop. We will end up with better weight then gas much sooner then you think. The theoretical max for aluminum 6 to 8 kwh / lb . or about the same as gas . The maxed out ice is probably using sub 10% for work of that 1 lb.
The ev world hasn't even began to tack advantage of all the teck. Like switched reluctance motors, cryo cooling, Volt type transmissions. The military / aerospace uses all this and more .


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## DanGT86 (Jan 1, 2011)

aeroscott said:


> How does the rotating mass show up on a dyno , only a very small part of the mass is effecting untimed hp. Mass relates to time to speed.


The dyno measures power by measuring the *rate* that the car accelerates a specific load. So time is in there. Its measuring power (work/time)

One of the loads slowing the rate of the loaded motor's acceleration is the inertia of the rotating mass. So the motor outputs say 420hp and things like friction and inertia induce drag on the motors acceleration resulting in a final number like 380hp to the wheels. 

When you put that car on the track it behaves like a 380hp car. It doesn't lose power again because the rotating mass is the same as it was on the dyno. It already was accounted for in the final power measurement. 

That's where I base my claim that two cars with identical dyno numbers perform the same at the track regardless of rotating mass because the dyno measurement was the final* net* result after all loses in the drive train.


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## aeroscott (Jan 5, 2008)

In that type of test .yes . I was thinking of straight hp as is the spec. hp
that manufactures state.


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## PStechPaul (May 1, 2012)

What really matters is torque transmitted to the wheels, or more accurately, thrust exerted in the forward direction from tangential forces of the tires on the track/road surface.

Horsepower only matters toward the later portion of the race, where there is both speed and torque. 

An electric motor and drivetrain can be designed to deliver maximum torque at all speeds which is just below (or perhaps a little bit above) the point where the tires lose traction and begin to spin. The power needed is thus pretty much proportional to speed, except at takeoff where all the power will be the losses involved to obtain the torque, and also as the speed increases there will be aerodynamic drag losses that add to the power needed.

What about an electric dragster with a 1500 foot heavy duty three phase extension cord? Unfair? You could allow the dragster to have a hose connected to a gas pump...


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## Karter2 (Nov 17, 2011)

PStechPaul said:


> What about an electric dragster with a 1500 foot heavy duty three phase extension cord? Unfair? You could allow the dragster to have a hose connected to a gas pump...


Well, if you are going to allow the EV dragster to be connected to an external power source, then it's only fair the ICE can use one also.....
....but I would pick a steam catapult !

But even with that 3 phase power cord, what sort of motor could you find to give upwards of 8000 hp...and ~~ 10,000 ftlb torque. .?......how heavy would that be ?


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## PStechPaul (May 1, 2012)

A 1000 HP (continuous duty) electric motor weighs about 3900 pounds, and produces 2900 lb-ft of torque. It can be overclocked and pushed to provide about 3 times that torque (possibly 10,000) and possibly as much as 8000 HP peak (which is how an ICE is specified)
http://www.temcoindustrialpower.com/products/Three_Phase_Motors_with_Base_Mount/M13278.html

But if you mounted that motor on a chassis to get a total weight of 5500 pounds, you could accelerate at 1G (22 MPH/sec) with just 936 HP at 60 MPH which would be at about the 3 second point. With 8000 HP, you would be able to accelerate at 3G (67 MPH/sec) at 174 MPH (also about the three second point). At an average speed of 90 MPH over 3 seconds. At 5 seconds it would be moving at 335 MPH and thus 170 MPH average in 5 seconds is just about 1/4 mile.

I'm just using my EVcalculator to arrive at these estimates. This works out to 34000 Wh/mile so the 1/4 mile could be accomplished with a 10 kWh battery pack.

Using other numbers, a 2G acceleration is 45 MPH/sec and 248 MPH also requires about 8000 HP. In this case an average speed of 124 MPH it would take 7 seconds to do the 1/4 mile.


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## Karter2 (Nov 17, 2011)

assuming all other vehicle weights are similar, you have a motor which you believe capable of equal power , but more than 3000lbs heavier than the Ice. 
(And how much of that weight is now rotating mass ?)
Then you have that 10 kWhr battery (200lb?) that has to supply 6000 kW !!
Isn't that a 600 C rating ?
Can we start being realistic ?


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## Hollie Maea (Dec 9, 2009)

PStechPaul said:


> A 1000 HP (continuous duty) electric motor weighs about 3900 pounds, and produces 2900 lb-ft of torque. It can be overclocked and pushed to provide about 3 times that torque (possibly 10,000) and possibly as much as 8000 HP peak (which is how an ICE is specified)
> http://www.temcoindustrialpower.com/products/Three_Phase_Motors_with_Base_Mount/M13278.html


Don't be utterly ridiculous. Industrial motor designers make no effort to make their motors light and compact, because they are stationary and its cheap and easy to just bulk them up.

A 1000hp continuous motor that was actually engineered for ev use would weigh a tenth of that.


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## aeroscott (Jan 5, 2008)

Hollie Maea said:


> Don't be utterly ridiculous. Industrial motor designers make no effort to make their motors light and compact, because they are stationary and its cheap and easy to just bulk them up.
> 
> A 1000hp continuous motor that was actually engineered for ev use would weigh a tenth of that.


 Thanks for pointing that out. 

8000 hp is the extreme edge of 100 years of development.
This same kind of development has been going on in electrics but not industrial but in military / aerospace . They have moved to cryo cooling
which moves us hugely along. In excess of 100 times smaller motors.
Refrigeration has been getting the efficiency of small units closer to the 75% that big industry gets when they liquefy hydrogen or helium .
IE;magnetic refrigeration, acoustic refrigeration 
What big industrial units do is to use many stages of cooling and then capture the energy of each compression cycle with turbines as the gases expand in the cooling cycles . These expansion nozzles are huge . I would think , to expand the gas to very low pressures to extract every btu .


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## PStechPaul (May 1, 2012)

It was just a quick example of the capability of an electric motor vs a gasser. I don't know if you could make a 1000 HP electric motor under 400 pounds, at least with that continuous rating and capable of boosting to 8000 HP for 5 seconds or so for a drag race. Perhaps with liquid cooling (but that also adds weight), or by designing it for 400 Hz. In that case you could have an electric drag racer that weighs about 500 kg (1100 pounds) that could accelerate at 2.2G (50 MPH/sec) for 248 MPH at 5 sec and peak power of 2000 HP. That would be 5 seconds for 0.17 miles and 2 more seconds at that speed for a 7 second 1/4 mile. 

According to https://www.dragtimes.com/ a Nissan 300ZX did a 7 second 1/4 mile. The fastest 1/4 mile time recorded for a top fuel dragster is 4.42 seconds at 336 MPH:
http://wiki.answers.com/Q/What_is_the_fastest_speed_ever_recorded_in_a_drag_race

So to get that with an EV, I use an acceleration of 3.5G (78 MPH/sec) for a top speed of 345 MPH at 4.42 seconds, with average speed of 172 MPH which is 0.21 miles. This requires 4400 HP at the top end but only 1900 HP at the average speed. Considering this as an average over the 1/4 mile 4.4 second race, it consumes about 8400 Wh/mile or 2100 Wh total. This would be 6200 amps at 250V. A 50C 120 Ah pack might do it. 

This is also where ultracapacitors might be well used, especially during the last couple of seconds where the required power is much higher. The peak 4400 HP is 3300 kW for, say, 2 seconds, or 6600 kJ. This is 211F at 250V, and if the batteries supply half, only about 100F might do the trick.

This might still not be practical, but with more serious engineering effort it might be. But I'm not particularly interested in drag racing, and there is already a fair amount of interest and work going on.


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## aeroscott (Jan 5, 2008)

very interesting numbers. 
with a gallon of liquid helium and a sub 100 lb. motor what kind of numbers would we get.


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## aeroscott (Jan 5, 2008)

I bet LHe costs a grand.


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## DanGT86 (Jan 1, 2011)

The top fuel dragsters use slipper clutches that slip at the beginning and transmit more power in the later parts of the race. 8000hp would be a a traction nightmare at low speeds. So they have an abundance of power throughout most of the run. This lessens the amount of time the Ev has to burst insane power levels. 

At the extreme level of the game it goes like this:
Gas dragster=make extra power and slip away what you dont need.

Ev dragster=make enough and carefully ramp it up

Hammerdown and swamp rat 37 will show us what is realistic!


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## aeroscott (Jan 5, 2008)

Big Dady has 6 motors 2000 hp. Get that down to 1 supercooled and save 4-500 lbs.


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## aeroscott (Jan 5, 2008)

I'm thinking 4-500 lbs. of lipro in big dady's car. 1500kw pack.


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## Karter2 (Nov 17, 2011)

You do know there is already a single motor EV dragster running a 2000+Kw pack ?
Infact it holds the NEDRA record currently.


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## aeroscott (Jan 5, 2008)

still running 400 volt , brush motors . wounder what the efficiency of these
motors are under these conditions .


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## Tesseract (Sep 27, 2008)

aeroscott said:


> Big Dady has 6 motors 2000 hp. Get that down to 1 supercooled and save 4-500 lbs.





aeroscott said:


> still running 400 volt , brush motors . wounder what the efficiency of these
> motors are under these conditions .


The only motor that could (theoretically) derive any benefit from being supercooled is a series DC type. Every other kind is magnetic saturation limited.

Also, pretty much all the materials used in motors get very brittle at cryogenic temperatures.

So this is just a bad idea all around.


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## aeroscott (Jan 5, 2008)

Tesseract said:


> The only motor that could (theoretically) derive any benefit from being supercooled is a series DC type. Every other kind is magnetic saturation limited.



I'm not making it up.Do you do any research on this . They are wound rotor motors/generators, but not brushed. Save us some time and Google it.

Also, pretty much all the materials used in motors get very brittle at cryogenic temperatures.[/QUOTE]

The austenitic stainless steels are extensively used in cryo work. Such as 304 . There ductility increases at cryo temps. Average high school science teachers wouldn't know this , but this is common knowledge in cryo engineering world.


So this is just a bad idea all around.[/QUOTE]

Just uninformed.


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## Tesseract (Sep 27, 2008)

aeroscott said:


> I'm not making it up.Do you do any research on this . They are wound rotor motors/generators, but not brushed. Save us some time and Google it.


I freely admit I did not do any research to back up my deep skepticism of your suggestion to immerse an AC motor in liquid helium to achieve extreme power output.

And going for a wound-rotor synchronous motor won't sidestep the saturation problem, sorry.



aeroscott said:


> The austenitic stainless steels are extensively used in cryo work. Such as 304 ...


And where, exactly, would one use 300 series stainless steel in a motor?


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## aeroscott (Jan 5, 2008)

Tesseract said:


> I freely admit I did not do any research to back up my deep skepticism of your suggestion to immerse an AC motor in liquid helium to achieve extreme power output.
> 
> And going for a wound-rotor synchronous motor won't sidestep the saturation problem, sorry.
> 
> ...



Do you also admit knowing nothing about the navy's and air forces work in this area. And other cryo electric work found on Google.
And on the srm thread comment, I had shorted my statement saying srm and standard vfd, I meant a particular srm vfd vers a standard vfd . If you watched the vid we were talking about , I think it would have been apparent . I think it's an important point about one particular type srm vfd advantages and needed to be cleared up.


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## Tesseract (Sep 27, 2008)

I apologize to the rest of the thread participants for attempting to stop aeroscott's wild claims of running drag racing motors in liquid helium. I just added him to my ignore list so I will be blissfully unaware of any further grammar/spelling challenged rants from him. Carry on.

EDIT... I was a bit curious about work done on cryogenic operation of AC motors and found this little blurb in a paper by Russell Shively:



> The environment within a dielectric liquid, at cryogenic temperatures, and the
> resultant effects of this environment on motor materials, has enabled engineers to develop
> motors that are capable of operating close to the magnetic limits of available electrical
> steels. Without heating or oxidation as a concern, *limiting factors to kW capacity become
> ...


Hence why I said I don't need to know anything specific about cryogenic operation of AC motors...


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## aeroscott (Jan 5, 2008)

I have dyslexia , always have . And a bad spell checker. Need to go back to MS .
The good news is that Google search has much more on cryo motors then in the recent past. In fact a small car powered by cryo motor 30 hp and 10% better range because of it. Looks kind of big .
Magnetic saturation , I had thought it was not impervious wall. IE; hot roded brush motors are running well into saturation.?
Saturation happens at the steel teeth , the teeth are there to aid in the magnetic field. But I found these large motors( 50 to 150 hp) form France and they had stator coils wound around a iron square( no teeth). Would this mean no saturation limit. They are PM rotors.Also some srm motors have no teeth.
Back to cryo motors in the link they say the iron teeth are not needed because 100 to 150 times stronger fields are generated. They use iron as a back to contain the field. 
Superconducting material set to improve performance of electric motors . 

I have never been able to get a eff. number on a hot roded brush motor
running maxed out.


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## aeroscott (Jan 5, 2008)

couldn't stop thinking about 100 X stronger fields , Teslas 411hp becomes 41,100 hp . I don't dare to dream that big , but?
That would end the gear box arguments .


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