Edmunds review

[TEG]

2008 Tesla Roadster First Drive

Lots of details, and a nice video, although this part seems questionable:

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"Tesla insists that the 1.5 package will enable the one-speed car to meet the Roadster's original performance target of 0-60-mph acceleration in 4.7 seconds.

We asked one of our own engineers to do a little number-crunching based on the few facts Tesla would supply, and we estimate that the new system will be rated at somewhere around 320 hp and 275 lb-ft of torque — a not-insubstantial boost of 30 percent."
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I don't know where they got that 4.7s target, nor how they came up with those powertrain 1.5 numbers.

 

[stopcrazypp]

2008 Tesla Roadster First Drive

Lots of details, and a nice video, although this part seems questionable:

==================================================================================================
"Tesla insists that the 1.5 package will enable the one-speed car to meet the Roadster's original performance target of 0-60-mph acceleration in 4.7 seconds.

We asked one of our own engineers to do a little number-crunching based on the few facts Tesla would supply, and we estimate that the new system will be rated at somewhere around 320 hp and 275 lb-ft of torque — a not-insubstantial boost of 30 percent."
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I don't know where they got that 4.7s target, nor how they came up with those powertrain 1.5 numbers.

I asked those same questions when I read that, so I'm glad you brought it up. Never heard the 4.7 number anywhere else either. Wasn't the roadster originally 248hp/211lbft? 30% boost is correct as calculated but a 72hp/62lb-ft isn't a small increase. In an exige, a ~30hp/30lbft bump shaved off .6 secs in the 0-60. Maybe they are guessing that's the kind of increase needed to keep the 0-60?

Also the lower range seems to be present pretty consistent in these first drives. But there can be many factors that cause this so I'm going to wait till the final production models are out and see some owner feedback on how the range is.

 

[BBHighway]

Why BEVs Are Different

None of the reviews really get into what I think is the best thing about BEVs:

No sparkplugs
No distributor
No ignition coil
No oil changes
No oil filter
No oil pump
No air filter
No valves
No lifters
No timing belt
No catalytic convertor
No muffler
No oxygen sensor
No EGR valve
No fuel pump
No carburettor
No fuel injectors
No alternator
No starter
No pistons
No piston rings
No connecting rods
No camshaft
No fanbelt

At one time or another, i have had every one of these parts fail or need to be serviced on at least one vehicle that I have owned.

Service items for the Tesla:
Tires
Brakes
Coolant
Coolant pump
ESS (aka battery pack)
Windshield wipers & fluid

 

[TedK]

Its amazing to me how inaccurate the "information sources" are on a regular basis. Hopefully someone over at Tesla will contact them and get it corrected.

 

[TEG]

Service items for the Tesla:
Tires
Brakes
Coolant
Coolant pump
ESS (aka battery pack)
Windshield wipers & fluid

There are probably a few more usual things like:
Gearbox oil
Wheel bearing grease
Alignment adjustments
And you have to wipe the grin off of the driver's face once and a while. :biggrin:

 

[TEG]

30% boost is correct as calculated but a 72hp/62lb-ft isn't a small increase. Maybe they are guessing that's the kind of increase needed to keep the 0-60?

If you take the 5.7 sec number for the current "one speed" and want to get to 4 sec then it is ~30% quicker. Perhaps they just did a simple calculation thinking they need 30% more HP? If so that would be wrong for a couple of reasons including the fact that Tesla intends to have a different gear ratio for the replacement "1.5" one speed gearbox. I wonder if Edmund's factored in the planned gear ratio changes? In any case the HP/Torque speculation seems like a bit of a needless exercise right now.

 

[TEG]

I also wonder about this part:

"Fortunately we were able to add a bit of juice with an hour's stopover in Tesla's shop, hooked up to the 70-amp, 240-volt home-charger unit that comes with each car (installation extra). But we still had only 23 miles on the range meter and a severe case of torque restriction when we headed out to the lightly traveled highway that serves as Tesla's unofficial test track for acceleration runs."

Could that be true? An hour's charge only gets you 23 miles and you are still torque limited?

"I would think with the 70 amp charger one hour would get you about 220 / 3.5 = 60+ miles of range. Maybe they stopped at Tesla HQ for an hour but didn't actually have the car hooked to the charger for nearly that long?

We learned again that the quickest your electric sports car will be is in the first few minutes after you leave the garage. It just gets slower after that until you return home again."

And what about that? I thought the Roadster offered nearly full performance until just before empty... I think the pack voltage does drop a bit between full and empty but this is the first I have seen someone say it actually causes a noticeable difference in performance. (Contrast this to a gasoline car where performance increases as the tank gets empty because of the weight reduction)

 

[tonybelding]

I also wonder about this part:
Could that be true? An hour's charge only gets you 23 miles and you are still torque limited?

"I would think with the 70 amp charger one hour would get you about 220 / 3.5 = 60+ miles of range. Maybe they stopped at Tesla HQ for an hour but didn't actually have the car hooked to the charger for nearly that long?

Something doesn't add up. Even if they were really hammering it and only getting 160 MPC, you can calculate 160 / 3.5 = 45.7 miles.