Tune the smart EQ and Twingo ZE to 95 PS and > 140 km/h or simply make it regenerate more

Some readers asked for it and now the time has finally come: With the support of smart eMotion, Steinbauer developed a tuningkit for the smart EQ. I have been using the finished product since two weeks now and of course I would like to tell you how it handles.

Anyone who knows the 4th generation smart electric drive, knows that this little city runabout has already an incredible acceleration coming from the factory. Between 0 - 50 km/h, it's faster than almost everything that everyday life has to offer. And that despite the fact that it's performance is always limited. The built-in electric motor from Renault can achieve up to 81 kW, but is limited to 60 kW in the smart (68 kW for Brabus).

There are two versions of the tuning kit:

The tuningkit is exclusivly beeing sold through smart eMotion and it's shop.

With the kit you'll get 10 % more power, torque, 50 % more regenerative breaking and even a higher top speed. Enough reasons to try the big 95 PS kit out and test how the little rocket is performing with the upgrade. For that purpose I build it in my 100,000 km old smart EQ.

It is particularly pleasant that the kit can be installed non-destructively and without tools in 30 minutes. It can also be easily removed and everything can be restored to its original state, as no cables have to be cut or control units reprogrammed.

Addition, April 2021:

The kit is also compatible with the Renault Twingo ZE, as it's powertrain is structurally identical. I've tested that myselfe.

But first thanks to all supporters:

First of all, I would like to thank Kristof, der smart eMotion reader lend his smart Edition One to Steinbauer for months so that they could use it to develop the kit. A remarkable move for which I would like to thank him on behalf of the entire community.

I would also like to mention Thomas Rebele from Tom's garage. His workshop has, together with smart eMotion, already been able to help many smart ED & EQ drivers with all sorts of problems and can now proudly say that all employees are driving fully electric smart cars. Also a special thanks to Ivo Jozinovic from Ivo FahrzeugTechnik. He took the time to dyno my smart. Sadly it was too cold while we measured, therefor the kit didn't do his highes performance. That's also why I'm using the measurements from Steinbauer in this Post.

The installation and the rough functionality of the kit

Installing the kit is not difficult as it comes with illustrated instructions. They show step by step how the kit is installed. In summary, it makes things a lot easier when you have a lifting platform at hand. Then you can easily look up between the battery and the inverter and find the right plug.

But first things first:

At the beginning you unplug the 12V battery so that the entire vehicle is voltage-free. Then, at best, you take the car up using the lifting platform and go to the correct plug on the inverter, which is clearly shown in the instructions.

And here we've got a great advantage of the kit for the smart ED4 over the Kit for the old smart ED3: No plugs have to be dissasambled. Steinbauer was able to source all plugs. You simply plug the car into the kit and the kit into the inverter of the car.

Now the module only needs power, which it gets from near the plug of the inverter. Now it's time to clean up. The cables of the tuning box are laid along the air conditioning hose.

Last but not least, the kit is stored under the trunk lid and, if necessary, the cables are fixed with a couple of cable ties (not included in the kit).

The task of the kit is to pick up the control signal from the smart, add approx. 10% and then pass the increased value on to the inverter. At the same time it keeps an eye on parameters such as the battery level and makes sure that nothing is overused.

How is the kit doing?

Immediately, you can clearly feel that the characteristic of the pedal has been changed. With the kit, the smart EQ is much more direct, especially in city traffic it now reacts very sporty. In addition, it has even more power than before. And while the factory tune starts to loose a bit power, the Steinbauer tune consistently pushes even more. This is also confirmed by Steinbauer's measurements:

Leistungskurve EN

The increased performance and the significantly sportier responsiveness ensure that the smart EQ is then even more fun. Personally, I really like the tuning, especially the sporty responsiveness of the motor.

What's also nice is the increased top speed. The smart runs 136 km/h (GPS) by the factory, with the tuning I measured 143 km/h (GPS), while the speedometer indicated 146 km/h. The top speed also seems to be somewhat dependent on the tire / rim combination.

Of course, the range at > 140 km/h is less than at 130 km/h, but the top speed of the smart EQ is not intended to achieve nominal ranges anyway.

Almost more exciting than the increased acceleration and top speed: The increased regenerative breaking

I particularly appreciate the increased regenerative breaking, originally the smart ED3 does not regenerate particularly strong, even when the radar based regen is deactivated. In connection with the tuning kit, however, the regen is significantly increased and the smart in OnePedal-Drive mode. It regenerates with up to 40 kW, which comes close to Tesla. In conjunction with the tuning kit, you'll get true one pedal driving and the mechanical brakes are only rarely used anymore. The smart then breaks so hard that it even nods down at the front when you fully lift you food of the power pedal. With the increased regen, the deceleration lane on the Autobahn is good enough to get from 140 km/h down to 70-80 km/h.

As with the tuning for the smart ED3, I asked Steinbauer again this time to offer a kit that leaves the motor power as standard and only increases the regenerative breaking. So if you only want increased regen, you can get that now as well.

Side note:

In order for the increased regen to develop its full potential, it is important to switch off the radar-based regen. You will find out what that is here in the FAQ. The shutdown of the radar-based regen is supported by smart itself and takes place via the on-board computer.


The Austrian tuning kit is priced well at 894,95 €, it is significantly cheaper than buying a smart EQ Brabus Ultimate E for over € 60,000, which even has less power than the kit. It also works without any problems in vehicles with the 22 kW charger and has the best OnePedal-Drive feeling you can get in a smart. What speaks in particular for the kit is that it can be easily installed by anyone and also is been removed easily without leaving any damage to the car.

Of course, such a tuning kit does not contribute to the longevity of the drive train. But since the motor itself is designed for this performance, I wouldn't worry about it. Inverter, gearboxes and the HV battery should also be designed so that they do not run at the absolute limit with the factory output. That's why I think the kit does not significantly shorten the lifespan of the car. Of course, it is up to you to decide whether you want to increase the performance.

Accordingly, it can also make sense that you only buy the small regen kit for € 644,95. This does not overuse any of the vehicle components but still increases significantly the regenerative breaking.

If you want to add something special to your smart from 2017 and newer, this kit is perfect for you. Of course the kit works in the fortwo and the forfour. Thanks to the increased regen, the range is not impaired and you still get about 120 km. Something the Brabus can't, simply because it has wider tires.


The Kit works in every smart ED4, this means it works in every smart made from 2017 till today. That includes smart cars from that era, which where named "smart ED".

The kit is also compatible with the Renault Twingo ZE, it works 100 % like it does in the smartEQfortwo and smartEQforfour.

EUR 894.95

EUR 644.94