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Tzero to Roadster to Model S and back to Tzero

Discussion in 'Roadster' started by deckofficer, Feb 18, 2015.

  1. deckofficer

    deckofficer Member

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    After returning to this forum after a 4 year absence, I have been trying to catch up this last week. This forum has quite a collection of knowledgeable EV folks, so is a good place to bounce some ideas. I saw Alan Cocconi's Tzero at the '97 LA Auto Show and was truly impressed with both the performance, and the range he was getting out of a bunch of yellow top Optima AGM lead acid batteries. It used 28 of these batteries which only have 44 ahr and because being lead acid had a much higher Peukert effect than lithium, so under heavy load had less than 44 ahr. Lithium has very little Peukert effect or voltage sag under the same heavy loads. OK, back on topic, this low energy density 14.8 kWhr bank still managed 85 miles with a 5000' elevation change.

    18 year old technology, yet 145 whr per mile urban, 171 whr per mile at freeway speeds. Battery energy density 38 whr per kg.

    This range increased to 200 miles with commodity lithium-ion cells of this time which has 1/2 the energy density of current cells. When Eberhard and Musk approached Cocconi and Tom Gage individually to prod them into taking the next step and produce the vehicle, Gage opted instead to introduce Musk to Eberhard and get back to work on his own projects. I would say that was the start of the Roadster.

    As Elon has said, the Roadster was a proof of concept minimum production run to validate a fun to drive EV, even though IMO Cocconi had already had that with the Tzero. I understand market demand, so the Model S was needed but I'm still a diehard EV nut with the hopes that sometime down the road a new version Roadster based on the minimalist Tzero would be built. At 171 whr per mile at freeway speeds with the reduced weight of the new 3.9 ahr 18650 cells comprising a 85 kWhr bank, gone is range anxiety. That is almost a 500 mile range and if you hypermile drive it, over 500 miles.

    When I drive cross country I plan on 800 miles before dinner and a hotel. Only a revamped Roadster built to be light and efficient could pull this off, 450 miles, 1/2 hour lunch while on a Supercharger, then 350 more miles to a hotel that can deliver 10 kW charge for overnight. And when those 400 whr per kg batteries are in production, you can skip the 1/2 hour lunch on the SC, and just drive 80 mph for 10 hours and bag a hotel for the night that recharges you the driver and your Roadster.
     
  2. TEG

    TEG TMC Moderator

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    If you dig through the forum and other sites, you can find a bunch more info about all of that.
    If Roadster was a proof of concept to get Tesla going, Tzero was just a prototype.
    It lacked safety and comfort features that would prevent it from any sort of general acceptance.
    So, looking at its' range capability isn't a totally fair comparison to production vehicles.

    But, yeah, it was a real nice piece of engineering that help inspire others to take the next steps to get us to where we are today.

    If/when Tesla decides to do another 2 seat Roadster car, it will not likely be as minimalist as TZero or even their first (Lotus based) Roadster.
     
  3. deckofficer

    deckofficer Member

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    Back them my EV was a 3 wheeled Cushman I converted to electric with (9) 8 volt golf cart batteries with only a 40 mile range at 40 mph without hills. They were able to climb the mountains that started right at their San Dimas location.
     
  4. tonybelding

    tonybelding Active Member

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    That's an interesting perspective. The Tzero was just an experiment, really, much like the Wrightspeed X1 or the electric Campagna T-REX or the Venturi Fetish -- the latter of which actually reached production, although I seem to recall only 25 were made. The problem with cars like this is that they aren't homologated and sold like normal cars, and they don't have a lot of credibility with the public -- or with investors. It takes a bigger production run, and an enclosed cabin with heat and A/C, and crash-testing, and airbags, etc., to have what most people would consider a "real car". The Roadster accomplished that, and it was also a vital learning experience for Tesla Motors.

    There are plenty of companies around the world today working on "electric supercars" of one sort or another: very expensive, very high-performance, very low production numbers if they ever actually reach production, which many of them probably won't. I have nothing against those kinds of efforts, but I'll never own one, and they don't move the needle for mass acceptance of BEVs. As for the future... Somebody will make a stripped-down BEV sports car of the sort you imagine. I doubt it will ever be Tesla, though. They have taken their business in a different direction.

    Personally, I wouldn't mind seeing a milder, more mainstream, and less expensive electric sports car on the market -- something like an electric Miata. It's the most popular sports car in the world, let's not forget. Mazda won't be doing that any time soon, but the MINI Superleggera could possibly be it.
     
  5. deckofficer

    deckofficer Member

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    Your right Tony, it is just my DIY nature that allows me to be tolerant of crude but effective approaches, as witnessed by the Track-T in my avatar. When changing out the drivetrain and posting the build threads on a few hot rod forums, I got flamed a lot for my ideas. Kept going with my ideas and had a hot rod that did 11.3 ET in the 1/4, broke 30 mpg @ 65 mph on a flat highway, and corners over 1.0 G.

    Like Carroll Shelby used to do, biggest engine in the lightest car with minimal creature comforts. Now that doesn't mean something as neanderthal as my T, but as a single driver (no passenger) 99.9% of my driving, I sure don't need a Model S. My "perfect" Tesla would be no bigger and much lighter than the Roadster, with the battery of the 85, the performance of the P85D at 1.5 times the range, at a cost of $60K.

    Am I dreaming?
     
  6. TEG

    TEG TMC Moderator

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    The Roadster tried to minimize weight as a priority. For instance, the carbon fiber body and aluminum chassis weren't the mainstream way to do things but they saved weight (but kept costs higher.) But it still weights a lot for a car of its' size due to the battery pack weight offsetting everything else. Battery improvements could help make a new gen Roadster better than the old, but I don't think Telsa wants to go back to those spartan roots. Roadster lacks all the neat stuff of the giant integrated touch screen in Model S. It even lacks power steering, which some purists love, but many drivers don't like due to heavy steering at low speeds. Tesla seems headed towards more tech (e.g.: self driving) and less into minimalist weight savings.
     
  7. deckofficer

    deckofficer Member

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    I understand and accept that Tesla's marketing is for wider acceptance by the car buying majority, it is just me and what a sliver of the market I represent to any automaker. In 2011 I bought one of the 194 Caddy CTS-Vs with a manual transmission. My taste in cars just isn't shared by others.
     
  8. TEG

    TEG TMC Moderator

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    Long ago I custom ordered a Lexus with every option except seats downgraded to base cloth that they really only intended for the few stripper models they planned to make to be able to advertise a low base price. The dealer didn't want to take the order, said I would kill the resale value... But it is what I wanted, and managed to get. Those seats held up great and I really liked them. Anyways, going with the sheep/lemmings isn't always going to satisfy everyone. Having different choices is nice. I like and appreciate most of the Roadster rough edges. I would like it if they made another trying to stay close to the original. I don't expect it to happen like that.

    Right now, lack of supercharging capability is one of the limitations of the original Roadster that is a bit hard to swallow as the Supercharger network continues to expand. There are some out there that think the original Roadster is one of the best cars ever made, and would never part with theirs, but many of them wish it could use the Superchargers.
     
  9. deckofficer

    deckofficer Member

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    Depending on your age, you could very well have a future collectible in the Roadster as you hit retirement. I think I'm too old to see if my V manual becomes a collectible.
     
  10. bart513

    bart513 Member

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    Maybe you have the knowledge to make the current Roadster more efficient and increase the range?
     
  11. tonybelding

    tonybelding Active Member

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    The Roadster has character. I've become attached to mine very quickly. I suspect it will always have its share of fans, even after becoming technically obsolescent. And that's what "classic" means.

    I'm sure the next sports car from Tesla will differ from the Roadster in many ways, and will be a more polished production. I'm just not sure how upscale it will be. Will it be a supercar in price and performance? Or will Tesla move toward something more Corvette-like? I would prefer the latter, but I suspect Elon will demand the former.
     
  12. ecarfan

    ecarfan Well-Known Member

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    I think the "next" Roadster will be targeted at the Porsche 911/Cayman sports car market segment, meaning a base price of around $80K, great performance and handling, and tons of options that can take it well over $100K.

    In other words, not a Miata and not a supercar.
     
  13. JRP3

    JRP3 Hyperactive Member

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    Sure, wait for the 3.0 upgrade package to come out :wink: Or wait even longer for the 4.0 upgrade package :biggrin:
     

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