Are you considering upgrading to a 2021 and want a definitive answer on whether or not it is quicker? I'll answer that question for you here.
As numerous websites have pointed out, when Tesla updated its configurator for the 2021 Model 3, the 0-60 time was reduced from 3.2 to 3.1 Seconds. Some speculated that this was just to account for the 5% power boost the car was given some time ago, but others thought there may be a power increase to explain the change.
Now, straight-line acceleration is not something we focus too much on when driving a road-course, however if you are considering an upgrade or in the market to purchase a Model 3 it's something you at least want to account for.
We brought the Model 3's out to NCCAR for some testing, and one of the questions we looked to answer was this. I'll link a Video where you can see the "Drag Races" we put together, but hard data paints a much more clear and accurate picture.
Here is a graph of the power output from both cars, and as you can see they are very similar. The 2021 put the power down slightly faster, likely from having marginally improved traction. The 2018 was sitting on the 18" Michelin MXM4's, so about as far from being a "sticky" tire as possible.
Peak power from the 2021 was 421.13kW at 53 MPH, whereas the 2018 was 421.45kW at 50 MPH.
Average power for the 2021 from 0-90 was 328.5kW, whereas the 2018 was 319.4kW. Again, this difference is most likely attributed to better traction.
We then ran several 0-60 and 1/8th mile tests in the 2021 to see if they were any faster than other 2018-2020 Model's. The best 0-60 we could manage was 3.36 (3.13 with 1ft Rollout) and the best 1/8th Mile was 7.42 @ 94.30 MPH. When comparing to the Dragy Leaderboard, we a fair bit off from the fastest for December's 0-60 (3.25/3.05) and 1/8th Mile (email@example.com).
In Conclusion, it is clear that the 2021 is not any quicker than the 2018-2020 Model 3 Performance. That being said, the 2021 does have a slightly larger battery pack - ours was delivered with 80.3kWh compared to the 2018's which were delivered with about 77.5kWh. Every bit helps on-track, so that is something to consider. The next thing we will need to determine is whether or not the new Heat Pump system is up to the task of cooling the Model 3 on the Road Course.