I posted this in a CPO thread earlier but it applies here
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1. a new Model S will always have the same or higher capacity battery as the top option than a model 3
2. a used Model S can pay some outrageous price to upgrade the battery pack to the new version no matter what year it is
3. if the upgrade price isn't a preferred option someone will always have the option of trading up to a newer Model S instead of upgrading the older Model S. This will have a cost also.
But ignoring upgrades of existing cars you have the situation where (
Model S options by year - a running history - Tesla Motors Club - Enthusiasts & Owners Forum)
2012 -2015 (pre April 2105) Model S only had 60 kwh and 85 kwh options
April 2015 to current adds 70 kwh and 90 kwh for Model S (90 kwh confirmed for Model X, unknown when a lower capacity will be added)
now lets extrapolate a little
Say in 2016 we gain a 75 kwh for Model X and Model S and a 95 kwh for both as well.
Say in 2017 Model S/X have a 80 kwh and 100 kwh
Say in 2018 Model S/X have a 85 kwh and 105 kwh
If the Model 3 has a 80% size and gets better efficiency from it then it gets similar range from an 80% sized battery. (you can argue that point in
300+ Mile Model 3?)
So say the 2018 Model 3 has a 85 kwh battery pack that gives it the same range as a Model S at 105 kwh and there is also a Model 3 with a 70 kwh battery pack that gives it similar range to a Model S with a 85 kWh battery pack.
You end up with CPO and used cars in buckets chronologically of
Model S60 pre AP (2012 to early 2014)
Model S85 pre AP (2012 to early 2014)
Model S60 with AP (late 2014)
Model S85 with AP (late 2014)
Model S70 (early 2015)
Model S90 (mid 2015)
Model S75 (2016)
Model S95 (2016)
Model S80 (2017)
Model S100 (2017)
Model 3 - 65 (range similar to a S80) - 2018 version
Model 3 - 80 (range similar to a S100) - 2018 version
Model S85 (2018 version)
Model S105 (2018)
I'll argue that much of the cost savings for Model 3 are in economies of scale and aren't just decontenting. A fully loaded Model 3 will be competitive to a comparably loaded Model S enough so that they'll be demand limited as usual.
I'm expecting the Model S of the second half of 2017 to have a equal pack in terms of range as a 2018 Model 3. I'm assuming the packs aren't interchangeable between S/X and 3 but are interchangeable between S and X.
So in 2018 I'm saying a new Model 3 will be a better car than a 2015 model S just because the motors/drive train components/fuses/inverters/charger/battery pack improvements will be significant and I don't think they'll decontent the interior enough to turn away people based on luxury.
I think this practically guaranteed improvement in range and component quality will be different enough from gas car improvements to make the S vs 3 comparison similar in 2018 vs 2018 but very different in comparing 2018 Model 3 to 2015 Model S.
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Now since that post I've watched the Baron conference interview with Musk and He added a comment about how the S will always be the platform for new tech and the 3 won't have the latest tech. We don't know if that means one year behind or two years behind but until the reveal next spring lets go with the one year back version.
Think about that for your Ludicrous mode question. If a 2015 car has Ludicrous mode a 2018 Tesla Model 3 will have it. Whatever tech is common in 2016 will be on the Model 3 even.
Keep in mind from the 691 HP threads that the battery limit for HP drops as SOC% drops. A model 3 with a smallest battery can still Ludicrous at 100% SOC but will get noticeably weaker at 50% SOC. Don't think that will keep people (Tesla and owners) from bragging about the ludicrous mode, the 0-60 times, etcetera. The Model S might have a bigger battery and might be able to do more runs at a higher SOC% but both S and 3 will do fast runs.
Maybe range scales better than acceleration and the note on the Model 3 should be
Model 3 - 65 (range similar to a S80, acceleration similar to a S70) - 2018 version
Model 3 - 80 (range similar to a S100, acceleration similar to a S90) - 2018 version
But I honestly don't know how well acceleration vs range will scale.