Many manufacturers set a top-speed limit on their vehicles in software. VMAX Off means removing or re-setting this limiter in the ECU software.
Why is there a speed limit?
Manufacturers set a top-speed limit on vehicles for various reasons. The main ones are the speed rating of the tyres, the manufacturer's internal policy for the vehicle type and the regulations of some markets. In most vehicles the limiter is not a physical barrier but a parameter in the ECU software, so it can be re-set with software.
Common factory limits vary around 180 km/h, 210 km/h and 250 km/h; much lower values are also seen on light commercial vehicles and some models.
How is VMAX Off applied?
After the ECU file is read, the parameter belonging to the speed limiter is analysed and, depending on the request, disabled or set to a new value. The job can be done on its own or requested together with a performance software such as Stage 1/2/3.
What removing the speed limit means
Removing the limit does not mean the vehicle will automatically reach a much higher speed. The top speed that can be reached is determined by engine power, aerodynamic drag and gear ratios. Once the limit is removed, the vehicle can accelerate up to this physical limit.
Safety and legal points
- The tyres' speed rating must be suitable for the speed the vehicle can reach
- Systems such as brakes, suspension and gearbox must be suitable for high speed
- Speed limits on public roads are set by each country's regulations and always apply
- High-speed tests should only be done in closed and safe areas
When creating a request
After selecting your vehicle in the panel you can add the "VMAX Off" option. Stating the vehicle's tyre speed rating and your intended use in the request note is recommended.
Frequently asked questions
It is possible on most vehicles, but it varies with the ECU design. You can see in the panel whether the option is offered for your vehicle.
No. Removing the limit does not change power values; it only removes the top-speed limit set by the software.
Yes. You can state the value you want in the request note.