The spare wheel test

… for the Model S, derived from a BMW X3 spare wheel space saver, went sort of well, except that the “Hubcentric Ring” is needed, not for centering, but to keep the wheel spaced and away from touching the Model S brake pad. Voilà.

Not for centering as advertised, but for spacing as needed

I’m going to substitute this with 5 of these, one for each bolt.

One per bolt should give enough clearence

Definitive tests will follow soon.

One disadvantage over the ring: each and every bolt needs one and managing 5 pieces is worst than managing one single piece. One advantage: no need to wait for the ring to arrive to do the final tests.

I have to check the way the wheel rests and spaces with this inexpensive fast solution, to be sure it properly solves the problem and works flawlessly.


Being busy…

… deriving a solution for a spare tire for the Model S. I hate the foam approach. I’m not alone. There are those who report a BMW X3 compact spare wheel as a solution. YMMV. Lots of info, some also more noise than info, that’s the Web. You have to love it, and you have to have the time to filter the “info” noise, noise really. That’s the bad part: too much time filtering the not so good info, or the bad info, and than you feel kind of lost.

The main thing: to be sure, positively sure, the solution works. To be positively sure the car is safely drivable. To be absolutly sure all the car specs are met. All this before trying the actual deed. After that doing a carefully planned and safely staged try. Validating the try is a must. Hopefully it will be done today.

Edit: just before 13:00 h today I bought 5 nuts to apply to the X3 spare wheel on the Tesla. It goes up to 300 Nm, so the specified Tesla 175 Nm goes very well with it. Nice.

On AP & AS

From a driver aledegily falling asleep, Tesla Updates states:
“Tesla has repetitively made it clear that drivers“remain engaged and aware when AutoSteer is enabled” and “must keep their hands on the steering wheel”. The car will emit sounds and display alerts when the driver needs to take over. In the event that the driver can’t be raised, the vehicle will activate its hazard lights and move towards the hard shoulder, where it will then stop.”

It is true the car signals repeatedly, in several degrees of importance and warning, that the driver must take control.

It is not true the car will “move towards the hard shoulder”. The car keeps itself in the same lane and, failing to get the driver’s control, it will come gradually to a stop with the hazard lights activated. In the SAME lane. It’s lame to state what the car does not do.

How to become a rich guy in one simple step

Take your hard earned money and instead of buying a small apartment take it to the Tesla Motors web site and spend it in the Tesla Model S your money can buy: you receive the car and instantly, I mean INSTANTLY (as soon as you start driving your dream car) you are skyrocketed into a rich guy. Seriously?! Yes. From a normal bloke you are “promoted” to rich.

The only company doing decent/good electric cars is Tesla. The rest are merely jokes: I tried to buy one EV from any single one of them (VW, Ford, Renault, Kia, Opel, Mercedes, BMW, …) before deciding that their comercial practices, their prices versus range and features, their engineering approaches, their ridiculous speeches and Public Relations reports and statements, their absolutely stupid maintenance and after sales support, did not deserve my hard earned money. So I riskily took a chance (Portugal does not have yet a Service Center) and bought a Tesla Model S. I did not know the surprise: I am now a rich guy. Ye, right.

Driving the Model S

Short trips, or long trips, it’s the perfect car: it tells the driver the range, where to charge, the traffic.

The GPS software takes into account not only the shortest route, but also the one with less traffic.

Once I saw the system change the route three times just based on the buildingup traffic, since it was rush hour: suddenly the best way was another way, and yet another one. This is the best car for someone that deslikes traffic jams, because of accidents or other causes, this car really helps avoiding them.

The Trip curve shows your Wh consumption along your driving, based on:

  • Length of the path;
  • Legal speed limits in every section of the planned trip;
  • Elevation along the planned trip;
  • The driver’s behaviour;
  • The car’s SOC State of Charge in the beginning and along the trip.

When driving, if legal speed limits are respected and accelerations are normal, not hard, in the end you will have almost exactly the SOC % it stated in the beginning. Or a bit more. The calculations are conservative. If you drive under the legal speed limits and softly with no hard accelerations, you will end with better than predicted final SOC.

Some examples of recent drives follow in the next pictures.

Planned trip, beggining
Same trip, soft driving, will end with 1% more of precalculated SOC. It marks where I am currently after 10 km. The curve was adapted above the original calculation: I’m behaving properly 🙂

This was a short trip just for demo purposes. A longer trip may give you much better ending SOC. The next example is a hard/harsh drive.

Beginning of drive, predicted curve
Lots of hard accelerations, the actual curve is under the projected curve; can you tell where the hard accels happened during the drive?
Each hard acceleration is marked (Photoshop manual edit): an inverted triangle shows fast energy consumption (negative slope) followed by some regeneration (positive slope)

The curve is updated in real time while you drive: you are all the time in full control of the energy saving or waste you are doing. Going at 140 at a 120 km/h section gives you worse Wh rate and the curve shows that instantly plotting under the initial calculated curve. To see Wh savings it’s enough driving 2 to 3 km under the legal speed limit, if the tarmac is dry. Wet tarmac gives you bigger consumptions.

A longer trip, 32 km long, with soft driving and always respecting speed limits: the driven curve almost matches the predicted curve

As far as I know the software is not yet applying in its calculations:

  • Air temperature;
  • Wind direction;
  • Air density;
  • Humidity;
  • Rain;
  • Wet or dry surface roads.

From these, rain and wet tarmac are the ones with most impact. Taking this into the software calculations would be a great improvement.