Audi makes a killer electric sports car

[rhitee05]

Shame this is just a concept car, but still incredibly awesome.

http://www.wired.com/autopia/2009/09/audi-e-tron/

Audi e-Tron:
4 in-wheel induction motors
230 kW total power
42.4 kW-hr liquid-cooled Li battery
3,319 lb-ft of torque!

According to the article, that's 20% more torque than an M1 Abrams tank, more than 5x as much as the Dodge Viper, and something like 12x as much as the Tesla Roadster.

Ridiculous. And awesome!

 

[liveforphysics]

My civic's engine running just naturally on pump-gas, no nitrous or anything makes 204ft-lbs at the crank.

First gear = 3.266:1
Final drive = 5.062:1

This puts us at 3372ft-lbs at the hub on a natural 4 cylinder civic that weighs 1800lbs.


An M1A1 tank is 134,800lbs, and can travel up a 60% slope at 4.5mph. This would imply the ability to apply something like 80,000ft-lbs of torque at the track drive hub if it were a 24" track drive wheel radius, but I think it's likely closer to 36", which would put it around 120,000ft-lbs.

A stock viper lays right around 4050ft-lbs at the hub in first gear.

 

[Tiberius]

As Luke has shown, torque is meaningless unless its specified where you are measuring it.

It's still not a useful number unless you also know the speed or rpm at which it is generated. There is plenty of room for specmanship. An electric motor has high torque at zero speed and it usually drops as it speeds up. A gas motor has max torque at a particular rpm and can't generate any below a certain speed. So you can always pick a scenario where the electric motor scores better, and one where the gas motor scores better.

The real thing to look for is the useful power and the efficiency at normal operating speeds.

Nick

PS. Nice car and all credit to Audi, but another case where a non-technical journalist has swallowed the hype.

 

[liveforphysics]

From the article:

"Minimizing weight is the name of the game when building an EV because it extends range. The e-Tron weighs 3,527 pounds. - Audi made extensive use of aluminum and carbon fiber in building the car — which is slightly smaller in every dimension than the R8 — and made the doors, roof and other body panels of fiber-reinforced plastic. Audi says the car has a 42:58 weight distribution. "

It's always funny to me how modern cars use all sorts of exotic materials just to wind up nearly twice the weight of a 5-seater wagon/hatchback civic. lol

Car weight = 3,527lbs (Audi claimed weight, which past history has shown is ALWAYS a huge lie with concept cars that are normally barely drivable tack welded together rubbish with a perfect body an interior for journalists to photograph...lol)
295/30series 19" tire = 25.47" tire OD.

3,319ft-lbs torque delivered through a 25.47" tire = 3119ft-lbs of peak forward thrust on a 3,527lbs car. = 0.88g's of possible acceleration.

3372ft-lbs of torque at the hub of my civic through my 24" slicks = 3372lbs of thrust on a 1,800lbs car. = 1.87g's of possible acceleration.

My grocery-getter 40mpg civic accelerates at 212.5% the rate of peak acceleration of the Audi concept car. And that's with no nitrous! On the jug, my civic makes another 170ft-lbs. lol

 

[Tiberius]

3372ft-lbs of torque at the hub of my civic through my 24" slicks = 3372lbs of thrust on a 1,800lbs car. = 1.87g's of possible acceleration.

Get up to about 3 x stall speed.
Apply about 3 ft-lbs rearwards torque on the control stick
Experience 3 G pull up
Look up at sky, look at horizon upside down, look down at ground
After about 3 seconds (though it seems longer) return to level flight.

Nick

 

[Malcolm]

A bit off-topic I know, but I remember reading somewhere that it's only possible to put around 0.5g of acceleration through the average car tyre before it loses traction. Does that generally hold true?

Luke, I've absolutely no experience of racing, so what percentage of your Civic's available torque do you think you can get to the wheels at take-off?

 

[liveforphysics]

3372ft-lbs of torque at the hub of my civic through my 24" slicks = 3372lbs of thrust on a 1,800lbs car. = 1.87g's of possible acceleration.

Get up to about 3 x stall speed.
Apply about 3 ft-lbs rearwards torque on the control stick
Experience 3 G pull up
Look up at sky, look at horizon upside down, look down at ground
After about 3 seconds (though it seems longer) return to level flight.

Nick

That sounds awesome Nick! I've only ever flown Cessna 152's and 172's, and when I got rough with them, they made terrible popping sounds like critical things were going to break off. lol I would LOVE to feel a sportplane sometime.

 

[liveforphysics]

A bit off-topic I know, but I remember reading somewhere that it's only possible to put around 0.5g of acceleration through the average car tyre before it loses traction. Does that generally hold true?

Luke, I've absolutely no experience of racing, so what percentage of your Civic's available torque do you think you can get to the wheels at take-off?

It holds very true for folks who don't know how to dial-in a chassis/tire combo.

On my slicks, I set my 2-step to hold my RPM's at 8,500, then a micro-switch on the clutch pedal activates the moment I let the clutch out, which opens the silinoid for stage1 of the nitrous to hit. I slip the clutch for roughly the first half-second before letting it lock 1:1 in first. The RPM's never fall below 7,500rpm if I launch correctly (from viewing the datalogs after racing), and if the chassis/tire pressure/ tire temp is all dialed in correctly, I can "hit it with the house at 15'.", which is to say I can apply all possible torque to the wheels right from about 15ft off the line.

To see a video example of what a proper engine/tire/chassis combo does in a fuel economy grocery-getter civic, the following video does a pretty good job. Notice the clown next to me does a huge excessive smokey burnout on giant slicks with a supercharged big-block V8, and then proceeds to have the same luck that everyone does who races me.
I'm the white civic in this video:

[youtube]amuXF6gJQRw[/youtube]

A friend civic just recently broke the 180mph mark in a street civic in the 1/4mile. 8.8 seconds an 180mph. He runs the same tire I do, but has roughly 1,400hp.

 

[Malcolm]

Nice. Looks like the other guy fell asleep

 

[Tiberius]

That sounds awesome Nick! I've only ever flown Cessna 152's and 172's, and when I got rough with them, they made terrible popping sounds like critical things were going to break off. lol I would LOVE to feel a sportplane sometime.

You generally need 3 to 4 G to complete a loop or a barrel roll. Most planes should take that. Even if you restrict yourself to to 0 to 2 G you can still do quite a lot if you do it smoothly. A Cessna 152 will go to 120 degree bank and back in a wingover without exceeding 2 G.

But my point was that if you want G force, use a plane. Even the humblest plane can offer you more G than a supercar.

Nick

 

[liveforphysics]

Nice. Looks like the other guy fell asleep

He bogged from inadquate launch RPM for his tire/chassis settings, then wildly over-compensated and spun the tires like a top. That is how a typical chump drives a powerful car.

AWD car's driven by chumps do the comical "squeek-bog" launch. It's like the opposite of the launch the guy did in that video. lol

 

[liveforphysics]

That sounds awesome Nick! I've only ever flown Cessna 152's and 172's, and when I got rough with them, they made terrible popping sounds like critical things were going to break off. lol I would LOVE to feel a sportplane sometime.

You generally need 3 to 4 G to complete a loop or a barrel roll. Most planes should take that. Even if you restrict yourself to to 0 to 2 G you can still do quite a lot if you do it smoothly. A Cessna 152 will go to 120 degree bank and back in a wingover without exceeding 2 G.

But my point was that if you want G force, use a plane. Even the humblest plane can offer you more G than a supercar.

Nick

Planes are awesome These planes were trainer/rentals that IMO had seen a lot of fatigue, and with no chute, I was too chicken/inexperienced to want to be the guy flying it when the "pop" sound is the last rivot going in that critical brace...

 

[paultrafalgar]

Shame this is just a concept car, but still incredibly awesome.

http://www.wired.com/autopia/2009/09/audi-e-tron/

Audi e-Tron:
4 in-wheel induction motors
230 kW total power
42.4 kW-hr liquid-cooled Li battery
3,319 lb-ft of torque!

According to the article, that's 20% more torque than an M1 Abrams tank, more than 5x as much as the Dodge Viper, and something like 12x as much as the Tesla Roadster.

Ridiculous. And awesome!

Imagine that concept was mated with this one:
http://www.youtube.com/watch?v=kTYiEkQYhWY
4 in-wheel motors and no weight outer skin or perhaps a three-way mix with this:
http://www.arielmotor.co.uk/
0-60mph in 2 seconds, but electric of course!

 

[liveforphysics]

This is Chris's grassroots effort at a turbo street civic. His 2 minute talk at the end isn't much worth hearing if you aren't a car guy, cause it will sound like blabbery mumbling rather than the subtle insight of a genius who is the first in the world to break the 180mph barrier in a street class FWD. You will notice the amount of steering input. He is running my slicks with 4psi in them rather than the 7psi that I run, because he is trying to lay 1,400hp vs 500hp (on spray).

He makes his own stuff, and he is running the block from a honda CRV with special steel sleeves machined and epoxied into it, and the cylinder head from a GSR integra heavily modified. He uses a very large turbo rather than nitrous to help it make power.

Enjoy

[youtube]mNjz2CxAuks[/youtube]

 

[paultrafalgar]

Yea, but not electric, not minimal skin, not in-wheel motor, not space-frame! In fact, not cosher!

 

[liveforphysics]

Yea, but not electric, not minimal skin, not in-wheel motor, not space-frame! In fact, not cosher!

lol. But 10x the power/weight ratio of the Audi from a home-built grass-roots street driven 1992 Honda civic hatchback is pretty wicked. I loved that the way that he broke the record was from a boost control silinoid line getting melted by mistake so the engine couldn't regulate boost correctly, and where most everything else would have blown, his engine held together and took the world record

But yes... it's pretty off-topic at this point.

 

[Lock]

Shame this is just a concept car, but still incredibly awesome.
http://www.wired.com/autopia/2009/09/audi-e-tron/

http://www.allcarselectric.com/blog/1043188_audi-unveils-a1-e-tron-minicar-in-geneva

Audi Unveils A1 e-tron Minicar in Geneva
By Eric Loveday
March 9th, 2010
The unveiling of the Audi e-tron marked a change from the company that was unexpected. Audi had previously claimed that they had no interest in electric drive vehicles and would focus on efficient diesel and gasoline options. Well, the e-tron rolled out in concept form and then was confirmed for production, which indicated that Audi had changed their plans.

Though the company still believes that the immediate automotive future will not be overtaken by electric drive vehicle, they also note the importance of following current trends.

The Audi A1 mini-car made its debut in Geneva this week. The European market will have several gasoline and diesel options to choose from when the vehicle is released. But what interests us is reports coming in about Audi's newest electric concept on display at the show. The concept, dubbed the A1 e-tron concept sport a unique powertrain setup and is perhaps the most talked about electric vehicle at the show.

The previous supercar based e-tron concept that we are familiar with is likely a low volume vehicle, but an A1 based electric could have high sales potential making it the company's first mass produced plug-in vehicle, if and when it reaches the market.

tks
Lock

 

[dozentrio]

AWD car's driven by chumps do the comical "squeek-bog" launch. It's like the opposite of the launch the guy did in that video. lol

That's me. I drive a slightly modified A4, and I can tell you, the squeek-bog is hard to avoid, without burning your clutch. A 1.8 litre engine with a teeny turbo doesn't exactly produce quickly-responding torque either...