How can you reprogram an electric vehicle?

For a long time, it was believed that the survival of the reprogramming sector was dependent on the existence of internal combustion engines. However, it isn’t true that the future disappearance of combustion engines will sound the death knell for reprogramming. WOT, which is deeply committed to R&D, has developed a specific programme to collect data from electric vehicles.

Although it’s obvious the ECUs in electric vehicles and their content cannot be compared to those of combustion engines, their data can be modified in view of improving an electric vehicle’s performance.

How is it technically possible to reprogramme an electric vehicle?

Every electric vehicle is equipped with one or more engine control units (ECUs) to establish the connection between the accelerator and the vehicle’s engine(s). There are also other ECUs, but the one we’re interested in is called the BMS (Battery Management System). It takes into account the battery’s temperature, charge, as well as other conditions to inform the ECU(s). If too much current is required, for instance, the BMS automatically regulates it to protect the vehicle’s range and the battery.

This BMS strategy aims to maintain a balance between preserving range and providing sufficient performance to guarantee a pleasant driving experience. This explains why an electric vehicle’s power gradually decreases as the battery is discharged.

How can you increase the power of an electric vehicle?

First of all, you need to understand that the design of an electric motor is much simpler than that of a combustion engine. The components are well known and don’t require the same level of expertise as for a combustion engine. As a result, new brands that were formerly unknown in the field of electric mobility are appearing on the scene. Today, when a manufacturer plans to launch an electric vehicle on the market, it must choose its electric motors, battery and various electric ECUs from a variety of existing products. It can therefore be assumed that the manufacturer selects the components it considers to be the most advantageous in terms of price, performance and targeted customer segment. This is why it is common to find the same features (e.g. similar power or battery capacity) in products from apparently unrelated manufacturers.

The manufacturer then sets a power level for its vehicles. Just like with internal combustion vehicles, it’s often simpler and more cost-effective to offer a single engine, then limit it electronically in order to create different versions of it. The wider the range of engines, the more technically feasible it is to limit performance.

Practical example: the Porsche Taycan

As you know, there are several versions of the Porsche Taycan: the rear-wheel drive, 4, 4S, GTS, Turbo and Turbo S. Given the diversity of the range, we considered that it would be unlikely for the manufacturer to develop a specific engine for each version.

To understand the limitations of the BMS, it is crucial to identify the battery fitted in the best performing vehicle. In this case, it’s the Taycan Turbo S, which is fitted with a 93.4 kWh battery as its standard. We considered it therefore likely that the BMS had been calibrated for this battery so it may provide a current capable of powering the Turbo S’ two engines. However, since everything was designed around the top-performance version, the difference in performance between the Turbo S and other models would probably be minimal, because it’s not a restricted engine – something we observed in our developments on the Turbo S.

In practical terms, this means that there are 5 models using the Turbo S’ battery:

- the Taycan 4

- Taycan 4S

- Taycan GTS

- Taycan Turbo

- the Taycan Turbo S

Our analysis revealed that all the models have the same electric motor at the front, with electronic limitations. The main difference between the models lies in the rear motor, which is less powerful in the 4 and 4S versions and cannot deliver the same torque and power as the ones fitted in the higher models.

Unleashed power

As you will have seen on our website, the performance after reprogramming is simply staggering. It’s even more impressive on the smaller models, which are largely limited. The Taycan 4 and 4S boast 740bhp and 820Nm of torque, while the GTS and Turbo S versions have 780bhp and 1050Nm of torque. Unlike the power figures announced by Porsche, which are only obtained in “launch control” mode, WOT’s reprogramming makes these performance figures an unrestricted reality!

Limiting consumption with driving modes

Of course, fuel consumption is a recurrent issue, and we are all aware of the shortcomings of electric vehicles in terms of range. As with internal combustion engines, it’s extremely difficult to optimise fuel consumption any more than manufacturers already have. However, it is a fact that more power generally implies higher consumption: the engines need to be well supplied, which can lead to a reduction in range.

Despite this, we can limit consumption by using the various driving modes available. Nowadays, most vehicles offer the option of selecting from different modes according to driving needs. This is the case with Porsche’s “Gravel/Range”, “Normal”, “Sport” and “Sport +” modes, for instance. The different modes affect factors such as accelerator pedal sensitivity and suspension stiffness, but the variations in power are minimal: Porsche decided not to modify power according to mode (with the exception of the “Range” mode). At WOT, we use the different modes to adjust power and suggest the mode best suited to the type of driving at hand. Here are the mode-based power variations we determined for our development Taycan 4S:

- Gravel / Range: 280hp

- Normal: 530hp,

- Sport: 680hp, and

- Sport+: 740hp.

Certification of an electric vehicle

Given that all reprogramming carried out by WOT is certified, it is legitimate to ask what criteria are taken into account for electric vehicles. Vehicle safety is a major concern for the authorities. It is therefore essential that the chassis be designed to withstand the additional power. Given that the Taycan’s chassis is based on the Turbo S version, there are no restrictions in this respect.

As far as emissions are concerned, no tests are carried out because electric vehicles do not produce any polluting emissions. However, a power consumption test is carried out by the MOT (TÜV). This involves analysing the voltage (V) and current (A) using test benches, both for the original vehicle and a reprogrammed one. At the end of the certification process, it was concluded that the Taycan did not any consume more power after WOT1 reprogramming.

Although the electric motors are not modified, a noise test is carried out on the road, in accordance with the European standard in place. This may seem irrelevant for an electric vehicle, but it is mandatory.

We hope you have found this article informative and that you’ve learned more about WOT’s certified electric vehicle reprogramming process.