Straight off the showroom floor, the Tesla Model S Plaid is already one of the quickest production sedans on the planet, but apparently, its factory performance isn’t enough for everyone. YouTuber Brooks Weisblat of the DragTimes channel recently tested a tuning module that promises to extract even more power from Tesla’s flagship electric sedan.
The test involved a 2026 Model S Plaid equipped with the Track Pack, allowing it to approach the 200-mph mark. With a plug-in tuning module installed, Weisblat recorded improvements in quarter-mile and half-mile acceleration, along with an indicated top speed of 204 mph.
The modification comes from SirHarrold, which offers software-controlled performance upgrades for the Plaid. Its adjustable settings can reportedly increase power by up to 10%, potentially adding over 100 horsepower without replacing the electric motors or battery.
Weisblat also demonstrated several unusual features, including adjustable suspension height and a dedicated burnout mode. However, the most interesting part of the video was the before-and-after testing, which revealed how much difference the extra power actually made.
A Plug-In Module Unlocks More Performance
Unlike conventional engine tuning, the SirHarrold system uses a small electronic module connected to the Tesla’s factory wiring. Weisblat demonstrated the installation beneath the center console, which took only a few minutes.
Once connected to a laptop, the module allows users to configure additional power in different driving modes. The software supports increases of up to 10%, along with a temporary boost function activated through a programmable button.
The system also offers suspension adjustments, including a stance mode that lowers the car while parked before raising it to a more practical driving height. Another feature enables front-wheel, rear-wheel, or all-wheel-drive burnouts, which Weisblat demonstrated during the video.
Quarter-Mile And Half-Mile Times Improve
DragTimes reported the following results with the additional 10% power setting enabled.
| Test | Without Tune | With Tune |
|---|---|---|
| Quarter-mile | 9.37 sec | 9.24 sec |
| Quarter-mile trap speed | 150.1 mph | 153.29 mph |
| 60–130 mph | 4.81 sec | 4.48 sec |
| Half-mile | 14.9 sec | 14.5 sec |
| Half-mile trap speed | 180.3 mph | 185.7 mph |
The quarter-mile improvement of 0.13 seconds might seem small, but gaining over 3 mph at the finish line is significant at this performance level. The half-mile results were even more impressive, with the tuned Plaid crossing the line approximately 5.4 mph faster.
These figures came from Weisblat’s own testing rather than an independent certification. The video also doesn’t include a dynamometer measurement confirming the claimed horsepower increase, although the acceleration results show a measurable improvement.
Nearly 200 MPH In Just 16 Seconds
During the longer acceleration runs, the Plaid reached an indicated 204 mph, with Weisblat reporting that it accelerated to approximately 200 mph in just 16 seconds. However, external timing equipment recorded a slightly lower maximum speed of around 198.5 mph.
Weisblat attributed the discrepancy to the car’s speedometer calibration, despite using tires matching the Track Pack specifications. The Plaid also reached its speed limit shortly after the half-mile mark, leaving relatively little difference between tuned and untuned full-mile results.
Even More Power Is Available
According to Weisblat, SirHarrold offers a more aggressive configuration capable of increasing power by approximately 14–15%. However, that version requires a substantially longer installation and carries additional risks, including potentially triggering the vehicle’s high-voltage pyrofuse.
The tested 10% configuration already delivered measurable acceleration improvements without major mechanical modifications. Its results demonstrate that even a three-motor electric sedan as powerful as the Model S Plaid can respond to aftermarket tuning. However, it’s unknown whether there are any long-term effects on reliability.