Roadster 4.0

[ecarfan]

4.5 seconds to 60 mph would be slower by half a second than the current non-sport Roadster. That ain't gonna happen. Under $60K probably won't happen either. They'll have to be under 2 seconds to out-perform the P100D Model S.

My point is that I would like to see a base Roadster at a lower price point, with good acceleration (4.5 sec 0-60 in an EV feels pretty quick) and great handling to show the world an EV sports car can compare favorably with much more expensive sports cars. And then have a high end Roadster that can blow them away.

Powered doors may be "useless" to you, but not to me. I love all the powered doors on my new X. Never imagined I would like them so much.

 

[daniel]

Just my opinion, but I don't think they can afford to build a new Roadster that doesn't out-perform the old Roadster.

 

[Johann Koeber]

Just my opinion, but I don't think they can afford to build a new Roadster that doesn't out-perform the old Roadster.

plus:
nice sliding roof
supercharging
nice interior
everything the M3 has

My guess the price will be above the original roadster.

Top of line might approach 250k$. Why not. It will compete with much more expensive supercars.

 

[Cloxxki]

If it's a $250K car, peculiar to give one away with 50 referrals. They'd effective lose $5K (plus other gifts) and $1K of discount and the cost of free unlimiteed SuC from the profit of each referral-sold S or X. Which most likely would have been sold without the referral anyway, although those who give out referrals are part of the community that save Tesla a lot of marketing expenses.

I can't imagine the new Roadster to be a complicated car with lots of options. If Tesla merely applies their "current" drivetrain tech, builds a new battery case as part of a lightweight (outsourced) chassis, it will be lightning quick off the line. But it would need an 80-90kWh pack at the very least to make the promise sub-2 0-60, and an optimal Roadster should manage with a smaller (crucially lighter) pack also. So, news flash, the cheapest cells on Earth are not the best for a true performance car. None of the performance BEV's hitting the scene over the past few years had true low cost cells. They choise something more sparky. 5.5C short burst power doesn't cut it. That's family car tech. Even if it works to get under 2 seconds to 60mph from 1 foot rollout, it will be a sluggish car in corners. Modern performance cars are measured in lap time. And that's Tesla's huge Achilles Heel. If not for its shear weight, then because the batteries are such a bad pick for track performance. The acceleration you get off a relatively cold start quickly vanishes after you've gotten the go-pedal to the floor for just a few seconds. Even the might SP100DL is not that quick around a lap. Let alone a long lap where heat buildup can catch up with it even more.
I follow videos of a master EV conversion engineer and racing driver who converted a Lotus using TWO Chevy Volt packs. It does much better than a Tesla for continued lapping, even the purpose built Tesla Roadster. Despite a smaller battery.
It would cost more, but I'm sure Tesla's partners prime battery partners Panasonic and Samsung could whip up a chemistry that sacrifices some energy density for power density, to be used in their now preferred 2170 form factor. Ending up with a pack that offers a sweet mix of good energy density for a range pack, great power output and resistance to overheating on track, at still an very agreeable cost/kWh. A matter of shifted priorities away from "cost over everything".

Can Tesla shift priorities to make the best roadster possible within a given target price? To be honest I am very sceptical. Making simple sound choices is hard on them. Other brands are spanking them on more and more fronts. Just the 360º parking view of an old Leaf make a Model S/X seems outdated. Many old flaws are just left as is. Most people don't even want to browse the internet on the 17" screen anymore. Cost, cost, cost. Very American. Smart allocation of resources nets such a better product that you increase value and profitability. There'd be no need to discount cars.

The more sparky cells a good Roadster IMO needs, would be very relevant for mass production Teslas. Prepare for higher charging power available from CCS and probably 3rd gen superchargers. Truly take on ICE cars for road trip convenience and A-to-B time.

 

[hsull8915]

Even if it works to get under 2 seconds to 60mph from 1 foot rollout, it will be a sluggish car in corners. Modern performance cars are measured in lap time. And that's Tesla's huge Achilles Heel. If not for its shear weight, then because the batteries are such a bad pick for track performance. The acceleration you get off a relatively cold start quickly vanishes after you've gotten the go-pedal to the floor for just a few seconds. Even the might SP100DL is not that quick around a lap. Let alone a long lap where heat buildup can catch up with it even more.

I am certainly not qualified to critique your review but there are a couple of points that I have an opinion on that I want to put out there. I do not believe it is universal that modern performance cars are measured in lap time. Stop any exotic sports car owner and ask them the 0-60 time, quarter mile, and any lap times. 90% of them will know 0-60 and proudly recite it, very few will know quarter mile, and less than 1% will even have the slightest interest in a lap time, let alone actually know one off the top of their head. Track performance stats are interesting to enthusiasts who watch videos all day but they are of little to no interest to the people actually shelling out the cash for these cars.

A matter of shifted priorities away from "cost over everything". Can Tesla shift priorities to make the best roadster possible within a given target price? To be honest I am very sceptical. Making simple sound choices is hard on them. Other brands are spanking them on more and more fronts. Just the 360º parking view of an old Leaf make a Model S/X seems outdated. Many old flaws are just left as is. Most people don't even want to browse the internet on the 17" screen anymore. Cost, cost, cost. Very American. Smart allocation of resources nets such a better product that you increase value and profitability. There'd be no need to discount cars.

The "best roadster possible" is incredibly subjective. Best to you may involve a lot of track stats and performance measures, while best to me means the thing is strikingly gorgeous and pins my friends eyes to the back of their heads when I stomp the pedal and run 0-45 like we got shot out of a cannon. IMHO, best to Tesla means they can A.) Sell it and B.) make money on it. I see no indication that they have any interest whatsoever in making a track machine, and I see no reason that they should be concerned with that either. In all honesty, since their stated mission is to accelerate the world's transition to sustainable energy, I don't see why they would even make another low production/high cost vehicle like a roadster other than as a hype machine. Looks, tech, and acceleration generate hype, not track performance. Just my two cents. Looking forward to seeing what they come up with since the first Tesla Roadster has been my dream car since I first heard they were making it.

 

[Doug_G]

I'd rather see a Roadster that could run a racetrack without overhearing rather than one that gets the fastest 0-60.

But fastest 0-60 is likely where they will take it.

 

[hsull8915]

I'd rather see a Roadster that could run a racetrack without overhearing rather than one that gets the fastest 0-60.

But fastest 0-60 is likely where they will take it.

I am definitely not saying it isn't a worthwhile pursuit! It would be very cool to see someone make a production EV that rivals a 911's track abilities, I just don't think it fits with Tesla's identity or goals.

 

[bolosky]

How about adding super capacitors for a power burst, combined with a small-ish battery for low weight?

Making a guess on mass and efficiency, it'll take about 500 kJ (about 140 Wh) to get the car to 60 mph. The best capacitors are about 15 Wh/kg, so with ~10kg of caps you could do a 0-60 without even drawing from the battery. Of course, once you did that you'd drop back to whatever the battery can do, so power comparable to today's Roadster. (Though, presumably, you'd keep the caps charged while driving so you almost always have power available unless you already used it and didn't leave time to recharge.)

If the battery charges the cap at 100 kW (which is certainly less than it'll be able to do, so not stressful), it'll take 5s to charge, so that's not a problem.

 

[Cloxxki]

How about adding super capacitors for a power burst, combined with a small-ish battery for low weight?

Making a guess on mass and efficiency, it'll take about 500 kJ (about 140 Wh) to get the car to 60 mph. The best capacitors are about 15 Wh/kg, so with ~10kg of caps you could do a 0-60 without even drawing from the battery. Of course, once you did that you'd drop back to whatever the battery can do, so power comparable to today's Roadster. (Though, presumably, you'd keep the caps charged while driving so you almost always have power available unless you already used it and didn't leave time to recharge.)

If the battery charges the cap at 100 kW (which is certainly less than it'll be able to do, so not stressful), it'll take 5s to charge, so that's not a problem.

The Panoz BEV LeMans 24h effort will have dual batteries, on chemistry each. There are no chemistries that truly strike the middle between "power" and "range" specific, for some reason.
There are plenty options for high power (both charge and drive) batteries.
Say, you have a 60kWh range pack which just lacks power. Say, Tesla would squeeze 300kW out of 2170's). The next 300kW you want for a really quick launch and quarter miles, would be too heavy in 2170. But power cells could deliver that power from a (much) smaller and on balance still lighter secundary pack. So you get, say, 65kWh that puts out the needed 600kW at the weight of a 80kWh range pack.
Under braking, the power pack addition would (more than) double regen capacity. It's much less susceptible to overheating and high cycling, could take care of braking in most all cases, and vastly improve efficiency around a track or "sporty" (BMW douche style) driving on public roads.
The power packs does most of the short bursts in power and regen braking, the range pack does the city and highway cruising. The two can interexchange energy as needed.

 

[bolosky]

The Panoz BEV LeMans 24h effort will have dual batteries, on chemistry each. There are no chemistries that truly strike the middle between "power" and "range" specific, for some reason.
There are plenty options for high power (both charge and drive) batteries.
Say, you have a 60kWh range pack which just lacks power. Say, Tesla would squeeze 300kW out of 2170's). The next 300kW you want for a really quick launch and quarter miles, would be too heavy in 2170. But power cells could deliver that power from a (much) smaller and on balance still lighter secundary pack. So you get, say, 65kWh that puts out the needed 600kW at the weight of a 80kWh range pack.
Under braking, the power pack addition would (more than) double regen capacity. It's much less susceptible to overheating and high cycling, could take care of braking in most all cases, and vastly improve efficiency around a track or "sporty" (BMW douche style) driving on public roads.
The power packs does most of the short bursts in power and regen braking, the range pack does the city and highway cruising. The two can interexchange energy as needed.

Wow, you can get 300kW from 5Kwh of batteries (60C)? I didn't realize that they'd gotten that good.

How do the high power batteries do for cycle life? They'd get cycled lots and lots of times with that design. Although, if they lost capacity but not power it probably wouldn't matter all that much, since you only need maybe 20% of the capacity for acceleration (to much more than 60).

 

[strider]

As for pricing, I've said it before and I will say it again - look to 911 pricing. $91k-$203k is the range I expect them to play in. I expect it will also be in that size/luxury range. The market for a hard-edged track car is insanely tiny whereas the market for a (very) quick car with a working hands-free phone and A/C is much larger.

I want power that is usable around town. I don't plan to track my car but I can use 0-60 quickness power every single day. I believe they would have to spend a huge amount of money and effort to rip off an insane Ring time vs getting the car down to sub 2-seconds. I don't see the payback. Sure you might lose the bench race to a Ferrari or other hypercar but as soon as you get out on a public road they are toast. And when I say public I mean keeping it near the speed limit.

Anecdote... The other night I was leaving a friend's house about 11pm. Almost no cars are out. I roll up to a stop light and there's an S90D next to me (quite rare where I live now to have 2 Tesla's at a stoplight together unless it's my wife and I). We look at each other and smile. Light turns green and we nail it until about 5mph over the limit. It was dead even. Next light we do it again, and then again. No one knew we were racing except us! We didn't wake anyone up, arouse the attention of the cops, nothing. I love EVs! Try doing that w/ any other car.

Don't get me wrong, I want a well-balanced car. But acceleration I can use every day - fast lap times? Not so much.

 

[bart513]

Great story @strider
I want the 0-60 super fast but I also want the range to take a nice long weekend drive. I'm sure that it will allow supercharging so that will be the saving grace!