Drag Times posted a video last week of a new Tesla Model S P90D with Ludicrous Mode enabled scampering to 60 miles per hour in a scant 2.65 seconds. That is seriously quick, especially since the car was equipped with standard 19″ wheels and all season tires. That raises the possibility that the same car with the optional 21″ wheels and performance rubber could go even faster.
Previously, Drag Times had set the benchmark time for the P90D with Ludicrous at 2.8 seconds. Which brings up this question — why is this car faster when it has the same specs as the prior car? Inquiring minds want to know. When it comes to anything Tesla, the place to find well informed, inquiring minds is at the Tesla Motors Club forum,where this latest video has sparked a lot of chatter.
Much of that commentary is fairly technical, but the general consensus is that Tesla has already started installing its new 100 kWh battery in its cars without telling anyone. Tesla has pioneered installing larger batteries in its cars but limiting their performance via software to lower power levels. For instance, the company now offers an entry-level Model S called the S 60, but it actually has a 75kWh battery installed that is software limited to just 60kWh.
Tesla offered a Model S 60 for a long time, but it had an actual 60kWh battery. The biggest difference with the new model is that is lists for $4,000 less than the old model. Buyers can elect to make it a dual-motor all-wheel-drive car for an extra $5,000 or unlock the full 75 kWh power of the battery for an additional $8,500. But at $60,000, it offers significant value. Although Tesla declines to release information about sales volumes, the rumor is the new S 60 has gotten a lot of new orders for the company.
The lads at TMC have convinced themselves that the added performance of the latest P90DL is due to it having a 100 kWh battery that is software limited to 90 kWh. That certainly explains why the “same” car is now quite a bit faster.
A battery charges slower the closer it gets to a full state of charge. For instance, a Tesla with an empty battery can get an 80% recharge in about 30 minutes at a Tesla Supercharger location. But getting to a 100% state of charge will take another 30 minutes or more. One of the advantages of the software-limited battery is it thinks it is a larger battery when it comes to recharging times. Therefore, the driver can get to an 80% SOC quicker in a software-limited battery. That’s an important benefit out in the real world and away from the drag strip.
There’s a similar effect when it comes to discharging the battery and providing power to the car to jump off the line.
Enjoy the video!
Source: Cleantechnica. Reproduced with permission.