Tesla gets its juice in a torrent of amps
I’m bombing around Hollywood on a Saturday night in an all-electric Tesla Roadster, a sick-with-torque, carbon-fiber mosquito with a half-ton of glorified camera batteries behind the seats. It’s a perfect night for cruising, cool and moonlit. The city lights drizzle over the silver car like Campari and creme de menthe.
As I nick down Vine, a Porsche Carrera C4 takes up a flanking position to my left and raps his engine -- a thick, ornery staccato rises, a murder of gas-powered crows. I, of course, have no engine to rap. The electric buzz the Tesla produces at low speed sounds like a toaster with a bagel lodged in it. I shrug sheepishly in the direction of the Porsche driver, sequestered behind tinted glass.
I turn west on Sunset and he follows me. He puts the Porsche door-to-door with the Tesla and guns the flat-six again. Oh, I get it. He wants to race to the next light. That’s too bad for him.
What transpires in the next 2 seconds is the heart and soul, the essence and spirit, of the Roadster. This is the trick this one-trick pony does better than perhaps any sports car on Earth. We in the business call it “rolling acceleration.”
At about 20 mph I nail the go pedal, and the power electronics module summons a ferocious torrent of amps, energizing the windings of the 375-volt AC-induction motor. Instantly -- I mean right now, like, what the heck hit me? -- the motor’s 276 pound-feet of torque is converted to dumbfounding acceleration. Total number of moving parts: one.
Street lights streak past me like tracer bullets. My little mental circuits go snap-pop with the thrust. God has grabbed me by the jockstrap and fired me off his thumb, rubber band-style. Wow.
Meanwhile, over in the Porsche, 19th-century mechanical forces are taking their own sweet time. The driver has to clutch, shift to a lower gear, and de-clutch -- a regime that takes about half a second if he’s talented. When he pushes on the accelerator pedal, the throttles in the Porsche’s throat open, the fuel injectors start hosing down the cylinders with high-test, and the variable-angle cams rotate to maximize intake-valve duration. The flashing fire in the cylinders can now apply its maximum force to the pistons.
But it takes precious milliseconds to overcome the inertia of the engine’s reciprocating masses -- the pistons, the rods and the crankshaft -- and to convert that force to torque (rotational force). Then that torque must pass through the clutch assembly and transaxle, and ultimately to the wheels, where it eventually gains leverage against the car’s overall mass. Only now is the Porsche accelerating.
By this time, of course, the Tesla has left it for dead.
Tesla Motors Inc. has had a short and tortured history, which I will not recapitulate here. Suffice to say the Silicon Valley electric car company, founded in 2003, has always seemed whipsawed between its own worthy ambitions and its nutty, headstrong arrogance. It turns out that creating a car company is vastly harder and more expensive than PayPal co-founder and jillionaire Elon Musk -- now Tesla’s chief executive -- ever thought. Only in the last few months have the first Roadsters trickled out to customers.
The company’s survival depends on securing additional millions in private capital and millions more in federal loan guarantees so it can build a new factory for its proposed S-series sedan, to be unveiled next month. We’ll see.
But what cannot be in doubt now is that the Tesla Roadster is, within very strict limits, a superb piece of machinery: stiff, well sorted, highly focused, dead-sexy and eerily quick.
Zero-to-60 mph acceleration is less than 4 seconds, which is Ferrari quick. Around a tight, technical racetrack, the Telsa will beat the pants off your garden-variety supercar.
And it’s tough, too. I only had the car for 24 hours but I caned it like the Taliban caned Gillette salesmen and it never even blinked.
During the Tesla’s long march to the market, there was debate in the blogosphere about the range the car could get on its 53 kilowatt-hour lithium-ion battery pack. Well, it turns out those discussions were academic, since the car is so small and brutal that you will give out long before the batteries do. Officially, you can go about 220 miles in mixed, moderate driving. Meet me in Paso Robles, at the chiropractor’s office.
The metabolism of the Telsa is very much like that of the Lotus Elise upon which it is based: lightweight (2,750 pounds), agile, uncompromised and indecently fun to whip around corners. The unassisted steering is race-car quick and precise, though the wheel loads up and fights back in high-G cornering.
The brake pedal feel is firm and progressive, betraying little of the system’s inherit artificiality. The “brakes” are actually a synthetic combination of calipers and the electric motor’s regenerative braking effect.
Is the Tesla worth $109,000? Well, if you’ve got it, it is, and apparently Leonardo DiCaprio, George Clooney, Matt Damon, David Letterman and Arnold Schwarzenegger all do. But I have my reservations.
The car is explosively quick under about 70 mph, but at speeds above that, the motor torque starts to evaporate. Above 100 mph the car feels labored, and this is right where a Porsche 911 Turbo is just hitting its stride.
The Tesla interior is rather bare and ungracious. The JVC stereo/navigation system, for instance, is something out of Pep Boys. The seats feel like they are carved out of whalebone. And, although the ride is surprisingly supple most of the time, hit anything bigger than a manhole cover and the suspension crashes like cymbals in the “1812 Overture.”
So, not perfect. But still amazing. One day, I predict, they’ll put a Tesla Roadster in the Smithsonian. For whatever missteps and overreaching Tesla has been guilty of, and whatever follies there are to come, the Roadster is here now, a divine spark, an animating lightning stroke of a whole new kind of car industry.
You have to respect that.
(BEGIN TEXT OF INFOBOX)
2008 Tesla Roadster
Base price: $109,000
Price as tested: $122,145
Powertrain: 375 Volt AC induction motor, air-cooled; single-speed, fixed-ratio transmission; rear-wheel drive
Battery: 53 kilowatt-hour lithium-ion battery pack, liquid-cooled
Power: 248 horsepower at 5,000-8,000 rpm
Torque: 276 pound-feet at 0-4,500 rpm
Weight: 2,750 pounds
0-60 mph: 4 seconds
Wheelbase: 92.6 inches
Overall length: 155.4 inches
EPA-certified range: 221 miles
Final thoughts: The Light of the Charge Brigade