Driven: 2009 Tesla Roadster v1.5
by Michael Harley on Oct 21st 2008 at 11:58AM 
Click above for high-res gallery of Tesla Roadster v1.5
Last January we landed an exclusive first drive of the Tesla Roadster. We were impressed, but well aware that the particular two-gear model we drove that wet afternoon wasn't identical to the version set to land in customers' hands later in the year. Last week, we were invited back to briefly test drive a genuine production model with the latest transmission and software updates (aka "powertrain 1.5"). Check out our round-two impressions after the jump. (Ed. Note: Sorry for the lack of live images, but we literally had about half-hour to drive the car before it was whisked away.)
Gallery: 2009 Tesla Roadster v1.5
Gallery: First Drive: Tesla Roadster
Tesla Motors invited us to visit its Santa Monica showroom last Friday for a quick sample of the latest Tesla Roadster, which we've dubbed v1.5 because of its new single-speed transmission. While Tesla went through some teething issues with its early two-gear transmission, this one is identical to the "problem solved" production version now being delivered to customers. Mid-mounted in the chassis is a 248-hp electric motor hooked up to the new single-speed fixed-gear Borg-Warner transmission.
The Tesla Roadster is actually built on a Lotus Elise platform. Originating in England, the bare extruded aluminum chassis is shipped to Tesla's brand-new assembly facility in San Jose, California. Upon arrival, it is mated with an electric motor (shaded in gray and located between the rear wheels in the above image), 6,831 individual microprocessor-controlled liquid-cooled lithium-ion battery cells (in purple), some seriously sophisticated electronics (in green), and all of the other go-fast components needed to make a proper sports car. With all 992 pounds of batteries hidden under the custom carbon fiber body panels, the Tesla Roadster weighs about 2,700 pounds.
A twist of the column-mounted key is immediately met with a few tones of acknowledgment from the on-board electronics signaling everything is ready to go. With a light press on the accelerator we glided out of the showroom without a sound. Except for the sheer absence of any audible feedback, the Tesla drives identically to an internal combustion automobile at low speeds (it even "creeps" if the brake is released). We pulled into the afternoon madness of Santa Monica Blvd. and crawled through the traffic as we headed towards the 405 freeway. We found the onramp straight ahead and absent of traffic, so smashed the accelerator pedal to the floor and 276 lb-ft of torque immediately launched us up to highway speeds. We exploded from a standstill to merging with moving traffic in about four seconds.
This is where it gets interesting. Unlike a typical internal combustion engine, the torque from an electric motor is 100 percent available from a dead start. So, while the combustion team needs to get rolling (or drop their clutch) to get in the "power band," the Tesla Roadster is already there. The torque curve is flat too – not dropping significantly until about 9,000 rpm ("redline" on the Tesla is 14,000 rpm). At highway speeds you hit the pedal and your head goes back. It only seems to lose the rush of uninterrupted power above 80 mph or so, when the falling torque curve meets the increasing wall of aerodynamic drag.
Around town, the Tesla drives like an electric go-kart freed from the incarceration of an indoor track. The non-assisted steering is perfectly-weighed once rolling, and the strong brakes boost confidence during short stops. The blinding acceleration made us forget about how we shoe-horned our 6'2" frame into the cockpit, or the absence of visibility past the B-pillar. With a giddy grin on our face, we really didn't care anymore.
Regenerative braking (sending power back to the batteries) mimics the engine compression we've grown accustomed to with "normal" cars. Lift off the accelerator, and the Tesla smartly slows down. We often didn't have to hit the brakes until much later in the traffic pattern. The company is quoting a range of about 244 miles per full charge (it went up with the new single-speed tranny). As highway driving – sans regenerative braking – uses up more electrons than stop-and-go driving, we think it would be fun to demonstrate that carving canyons in a Tesla is more efficient than driving to Bakersfield.
While the pure electric car sends chills down the rigid spines of traditional gasoline-belching purists, we are happy to report that there is no need to pop tranquilizers anymore. Our short reintroduction to the sporty production Tesla Roadster reveals that the electric car does indeed goose our enthusiast glands, and we can't wait to get our hands on one for an extended First Drive.
Reader Comments (Page 1 of 2)
imirk 12:12PM (10/21/2008)
you know... I think they muffed it with getting this to market on time, but its still sexy, I really like the interior, I just wish it didn't cost as much as the ZR-1, not that I could afford either in good conscience.
Reply
RacerX 8:58AM (10/25/2008)
Just think how many folks will get run over by silent cars....Nader will ask for front mounted woofers...Loud pipes save lives!
Dondonel 12:17PM (10/21/2008)
I don't see how that bulk of weight over the rear wheels helps the handling. The battery pack + motor weighs about 3 times more than the IC engine + fuel tank in a normal Elise. Poor weight distribution and high center of gravity do not make a good recipe for a sports car. Has anyone taken this car to the track?
Reply
ckm 12:27PM (10/21/2008)
Actually, most of the weight is right behind your head, between the rear wheels and the back of the seats. The motor is pretty small (think of one of those micro-kegs) and the electronics don't weigh that much.
The bigger deal is that the chassis was stretched about 6 inches.
mr996turbo 12:24PM (10/21/2008)
ive heard recenty telsa is bankrup!!
Reply
EskimoPie 12:27PM (10/21/2008)
Dude, I'm pretty sure they're not bankrup.
mr996turbo 12:36PM (10/21/2008)
well DUDE!!! thats what was said on fastlane daily which is preety good source for car imformation. how are most car companys doing write know......duuuuuuuuu
Wintrode 12:52PM (10/21/2008)
First off it's bankrupt. Can we agree on that? Right (See, that is the correct way to indicate an affirmative, not to trace or form (characters, letters, words, etc.) on the surface of some material, as with a pen, pencil, or other instrument or means; inscribe: Write your name on the board. ).
You must be reffering to this:
http://www.autoblog.com/2008/10/15/breaking-layoffs-and-executive-shuffles-at-tesla-motors/
Did you think that Tesla would be immune to the current economic times? They don't have pockets as deep as the big 2(3), but will be OK, once their DOE money becomes accesable.
Very exciting news...now if they can make the costs come down, I would be all over one.
sk 1:11PM (10/21/2008)
Maybe Telsa is bankrupted, but Tesla is not.
Bear Report 1:32PM (10/21/2008)
If Tesla ran out of my money can't they just do a reunion tour?
EskimoPie 1:40PM (10/21/2008)
Actually Tesla was bankrupt wasn't he? After Edison won out didn't Tesla pretty much loose everything?
Torqued 3:45PM (10/21/2008)
"ive heard recenty telsa is bankrup!!"
ive = I've
recenty = recently
telsa = Tesla
bankrup = bankrupt
Congratulations! You're 2 for 6 in word-spelling today. Maybe tomorrow we can work on punctuation.
mr996turbo 6:29AM (10/22/2008)
ha ha sorry i don't type well because i don't sit behind a computer all day. i can say this you get to read about thease cars i get to drive them ps please chk 4 typiing errrs...lol
Elux Troxl 12:34PM (10/21/2008)
Tesla: the new Delorean. Hope they don't resort to the same alternative financing scheme as John did.
Reply
cowbell 12:54PM (10/21/2008)
At this point, Tesla probably wishes it was successful as Delorean.
John Delorean's company produced over 9000 cars. Tesla had delivered 27 cars as of September. Incomplete cars at that... (temporary transmissions)
It seems Tesla's plan as an automaker is to take orders at $100,000 a pop and the churn out press releases.
m 12:47PM (10/21/2008)
It creeps when you let off the brakes? Why would it do that? My conventional car doesn't do that. It doesn't go until I tell it to. I don't care what people with torque converters have gotten used to, this is wasteful and stupid. Besides, people buy this car because it's different. So why put stupid stuff like this in trying to make it the same?
And why should regenerative braking kick in when you let off the accelerator? When you let off the right pedal, it should coast. When you indicate that you want to slow down by touching the left pedal, it should use regenerative braking for let's say the first half inch of pedal travel, then the service brakes kick in.
Reply
imirk 1:24PM (10/21/2008)
You're getting confused, you automatic car is the one that does not compression break and coasts really nice when you let off the gas, unless you are in the habit of pressing that third pedal every time you let off the accelerator. However I agree that they are doing this to blend in, ideally these would be customer selectable, and changeable depending on your mood/preference, since they both have to do with the electronic controls of the car.
Also it should be all regenerative breaking until it senses impending rear traction loss (in reverse Yikes), and then augment with front brake calipers, although I don't how much torque breaks put on the wheel I'd assume it is dynamic depending on wheel velocity.
m 1:33PM (10/21/2008)
The torque converter comment was only meant for the first complaint.. ;-)
My guess is that the limit to the regenerative brakes is the limit of charge acceptance of the batteries.
The problem the braking strategy both of us are suggesting is that the car will oversteer like crazy. It would have to be used in conjunction with a pretty good stability control system that will transfer that braking power forward when it senses oversteer.
Red 1:45PM (10/21/2008)
A car creeps forward when it's in gear and the brake is depressed (automatic). Considering, for all intents and purposes this is an automatic (sorta) vehicle, it should creep forward. Hence, the creeping. Manual transmission vehicles will creep forward if the car's in gear, depending on how much you've released the clutch pedal.
As far as the regenerative braking kicking in, if your foot's not on the gas, you obviously have no need to accelerate. Therefore, the parasistic braking system SHOULD recapture that energy since it will have to reuse it to re-accelerate the vehicle, etc.
m 2:00PM (10/21/2008)
An automatic doesn't creep forward just because all automatics should creep forward. It creeps forward because it has a torque converter putting drag on the engine all the time. It wasn't a design intent. It was a side effect of a non-ideal mechanical system. The roadster doesn't have this problem, and is just artificially reproducing the effect. Requiring you to stay on the brakes just to sit still by keeping pressure on the hot brakes isn't particularly good for your rotors either.
As for the regenerative braking, letting off doesn't mean you necessarily need to slow down. Maybe you're going down a hill. You don't want to stay on the pedal and accelerate down the hill. You don't want to touch the brakes (regenerative or otherwise) and waste energy. You just want to stop current to the motor so that no additional energy is being used at that moment.