RS 4.0 - The Apex

The RS4.0 is the latest High Performance Lego car from Alternative Engineering. All the experience gathered in the last 5 years of constructing has led to this benchmark and made it what it is: THE APEX.


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Insured worldwide tracked shipping.

​​In STOCK: Shipps in 1​-​5 days after payment!

Note that Alternative Engineering is not responsible for any imposed customs duties and fees in your home country.

RS 4.0 - The story

What was the RS 4.0 supposed to be?

Our creations are based around one or multiple key improvements. In the case of the RS 4.0, Christoph our head engineer and founder focused on 3 things during the design and construction process. After approximately 3 months of conception, construction and testing, the result was better than ever imagined. The RS 4.0 turned out to take everything onto another level and comes closest to handling like a hobby grade RC car.

  • Stiffness & Stabillity
  • Handling
  • Controlled Power


  • Power: 150 – 300W
  • V-MAX: 75 Km/h
  • L/W: 40cm / 26cm
  • WEIGHT: 970g
  • 4WD

Improvements over it’s predecessor

New Engine

First of all let’s take a look at the engine. The new engine in the RS 4.0 provides 30% more power than the old one. Using 2s Lipo batteries the engine can deliver around 150 Watts of power. To give you an idea of how powerful that is, you can see a graph comparison between a normal LEGO XL motor and the engines being used in my models.

Middle Differential Unit

The most complex feature added in the RS 4.0 is the middle differential, which has a massive impact on the handling of the vehicle. The difficulty during the design and construction process was that 100% of the engine power is running over it whereas on the front and rear differential the power is divided. My solution was to power the middle differential from both sides with a gearbox unit.


The Chassis was completely redesigned to make it much sturdier and stiffer. As a result, the RS 4.0 is definitely the tank out of all models.


Another big improvement comes from the suspension. The suspension travel was increased to 24mm which allowed me to make a softer setup. The result is a much better handling on rough terrain. And there is more on the suspension. The RS 4.0 is driving with 8 shock absorbers instead of 4 to provide a more evenly distributed shock load on each wheel suspension.

Precise Steering

The front end and the steering were completely redesigned to improve the handling even more.


Our​ main instructions​ ​are manually made with Studio​.io 2.0 ​a br​and-new LEGO designing software. The Instructions are of high quality and easy to follow​. The ​motorization part is the eas​iest! ​Two videos w​ill lead you through the integration of the high performing electronics in under 10 minutes.  We additionally provide PDFs with maintenance and driving information.


  • LEGO Digital Designer 3D Model
  • ​ manually made 400 step instruction
​Two ​instruction ​videos which will lead you through the motorization process of your model.

Parts Set

Alternative Engineerings LEGO SET provides a building experience right out of the box like you are used from normal LEGO Sets. The Set containing out of 100% original LEGO parts is counted by hand to prevent any missing part.


In the Plug & Race Motorization Set everything has already been done for you! The Set containing out of quality RC electronics is ready to be installed in any of the four RS models in less than 10 minutes.

Since I started challenging real RC cars 5 years ago I couldn’t find a Lego or plug and play RC motorization that fit my needs. So I started configuring my own. My plug and race Motorization set makes no compromises in terms of weight, power, reliability and range!

​3D printed adapters

​To ensure a seamless integration into LEGO Framework all Alternative Engineering sets come with custom 3D printed adapters. The high performing 3rd party electronics can be plugged in like you are used with the LEGO ​power function ​parts.

​One of the two integration parts of the servo motor which is responsible for steering the car.

​The motorization is already plugged together waiting to be installed in your car or MOC.

2,4 Ghz Radio Control with 500m Range

The Radio control ​is of high quality and fits the needs of all Alternative Engineering RS models perfectly!

 Radio Specification:

  • ​2.4Ghz system
  • 2-channel radio
  • Ergonomic grip
  • Internal antenna
  • 3-channel receiver with “failsafe” function

High Performance Brushless Motor

The core element which makes my cars upstanding from normal LEGO cars is the high performing brushless motor. It has to be very light, powerful and small to make the often considered impossible possible.


  • Max.continuous current: 18A/30S
  • Max.continuous power: 150 W
  • Weight: 39g
  • Max.lipo cell: 2-3S

Lipo Battery + Charger

To provide the needed 30 Ampere for the brushless motor I am using a 7,4V drone battery with a leading power-weight ratio. To enhance the battery lifetime of around 500-1000 circles a balance-charger comes with the Set.

Electronic Speed Controller

With the 30A electronic speed controller it’s possbile to have a steppless throttle and drive backwards. Advanced drivers can also configurate a auto breaking function.

Steering Servo

After all, a powerful car has to be controllable. The 4,5kg strong metal Servo provides fast and precise Steering. All RS models are able to change the steering direction in 0.14 sec.

Goodies & Special offer

The Alternative Engineering Plug&Race Motorization Set is installed in less than ​10 minutes in each of the 4 RS models. The LEGO connectors are already mounted on the motor and servo, the plugs are already soldered. Additionally a lubricant is shipped to provide endurance on fast outdoor runs.

SPECIAL OFFER: One additional lipo battery for double drive time​.

Includes one additional lipo battery. You can change the battery from the car in less than 1 minute. The plug is already soldered and ready to provide power!

Insured worldwide tracked shipping.

IN STOCK: Shipps in 1-2 days after payment!

Notice: Alternative Engineering is not responsible for any imposed customs duties and fees in your home country.


What's the difficulty of building a LEGO car using my instructions?

Which 3rd parts are used for the motorization?

How can you contact us in case of uncertainties?

How much is the shipping and to which countries it's possible to ship?

How long do I have to wait for my ordered set?