Or put an electric engine in an Ariel Atom
http://wrightspeed.com/about/x1/
They are also selling electric engine swaps for trucks.
Or put an electric engine in an Ariel Atom
http://wrightspeed.com/about/x1/
They are also selling electric engine swaps for trucks.
That car looks awesome, but surely they can greatly improve its performance/efficiency by doing some sort of aerodynamic improvements? Put some sort of clear plastic/lexan shell around it so that you won't loose much of the car's character, but gain helluva lot in aero efficiency. Give it that see thru swatch look or something. Anyway, regardless, it looks great and looks like it drives great!
1. Ever-more-powerful electric motors backed by battery packs charged by onboard turbodiesel three-cylinder 1.0L engines and grid-based charging systems.
2. Stuff 'em into newly designed FWD 5-door hatches and RWD 4-seat coupes utilizing a shared platform (AWD optional? Too heavy/inefficient?).
3. Profit.
Using electric motors takes away some of the heavy/inefficient aspects of AWD, since you can eliminate transfer cases/driveshafts/etc.
Whoomah!
Good point.
It takes 90 ft-lb of twist + "push to pass" from the electric motor to move the heavy Volt (3,800+ lbs.) around. I'm confident that could be achieved in a 1.0L turbodiesel triple (or smaller). Hilariously, the Chevrolet Spark EV generates 400 ft-lb. of electronically limited combined torque. I don't care how you do it, that's power!
Here's hoping that someone takes that drivetrain and does something really great with it. Flip it around and drop it into a Mk I MR2. Just... something!
Actually it torque.Originally Posted by novicius
Chevrolet Spark EV generates 400 ft-lb. of electronically limited combined torque. I don't care how you do it, that's power!
Power is better.
You can have any engine generate as much torque as you like just by using gearing.
It's just that it might only be at 1rpm and of little practical use.
Power is the ability to produce torque at revs.
Important if you want your vehicle to accelerate at a speed higher than 1 mph.
It's not *quite* that black & white, especially where electric motors are concerned. Unlike ICEs that produce a torque curve - starting at zero and increasing towards a peak before tapering off - electric motors produce essentially their maximum torque regardless of what speed they are at up to their maximum speed. ICEs rely on gearing because they produce effectively no torque at 0rpm - gearing allows them to get moving with the meager power they have available. While it's true there is a additional benefit to gear reduction with higher engine speeds, that additional power comes at the cost of NVH. The current batch of EVs have no gearboxes - they are direct-drive. They don't have a problem starting because they have full torque available. They don't have problems with NVH because they don't spin that fast. Academically, yes, they potentially suffer at high-speed acceleration vs. ICE-powered vehicles, but in the common operating window - 0mph to about 90mph - they aren't lacking. Our 500e is a direct drive motor with 150 (electronically limited) lb ft of torque and it out accelerates the much lighter 1.4l gasoline powered version even with a 6-speed gearbox. In the 1/4 mile, the ICE will barely run away from the electric only because the electric has a top speed of about 84 (IIRC) mph; the remaining six or eight miles an hour the gasoline version offers doesn't come into play hardly ever for most people. Sure, you could gear up an electric motor just like an ICE, but that adds loss, complexity, weight, and maintenance that isn't going to benefit most people most of the time.
I thought electric motors were constant power, not constant torque, hence why they jump off the line but run out of steam at the top end, so to speak, with only the one ratio. If they had maximum torque at all revs, they would have *great* power numbers, not die off as revs increased.
Get that weak shit off my track
Tesla Model S torque/power curves. Looks like the torque is limited until 40-50 mph where it drops below the torque limit for each model, then just continues to drop. At first it drops consistently with the rise in revs, so power stays constant, but then the torque drops faster than the revs rise so power goes down as well.
Last edited by Kchrpm; February 13th, 2014 at 02:03 PM.
Get that weak shit off my track
Torque is the twisting force, the only thing a motor can produce whether ICE or electric. Horsepower is a rating of work over time, a combination of that torque and speed.
That Tesla graph shows exactly what I'm talking about - full torque at 0rpm and consistent output within its operating range (which is apparently up to about 50mph). After that, you're outside its range and torque drops off fairly dramatically. Since HP is always the combination of torque over revs, HP builds perfectly in lock step with the consistent torque output, then drops off perfectly once the motor exceeds its optimum speed.
Electric motors have an inverse relationship between torque and operating range. You can build motors that make big torque but they will have a small operating range, or you can build motors that make less torque but have a wider operating range. It's always one of the other. On the Tesla Roadster, they tried to build the latter and couple it to a 2-speed gearbox but that ended in disaster... the motor kept shredding the gearbox. On the S, they built a low-speed, high0-torque motor and took out the gearbox. That's the route all EVs have taken because it handles the bulk of humanity doing the bulk of their driving while shedding complexity and a maintenance point.
I think - but am not sure - the reason Tesla originally did the 2-speed gearbox is because they couldn't figure out how to control the temperature of the motor/batteries in that big torque/low speed/high draw scenario. That got fixed - maybe by them? - with the modern liquid cooling scenario we have now.
Or, at least, that's my understanding of this whole situation!
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