Citroen C3 ERX

The Citroën C3 ERX is the world's first all electric race car based on a Rally2 platform and tailormade for EV customer motorsport. Equipped with a FIA certified STARD EV powertrain, it is perfectly suited for rallycross, hillclimb and any other national and international sprint races.

The Citroën C3 ERX is the world's first all electric race car based on a Rally2 platform and tailormade for EV customer motorsport. Equipped with a FIA certified STARD EV powertrain, it is perfectly suited for rallycross, hillclimb and and any other national and international sprint races.

Citroën C3 ERX core values are shared with the Rally2 version : performance, reliability and cost efficiency. Citroën C3 ERX combines the best of two worlds : the successful Citroën C3 Rally2 chassis and the Austrian EV motorsport pioneer STARD´s (Stohl Advanced Research and Development) groundbreaking REVelution EV powertrain. This vehicle is the world's first true road car based customer electric motorsport vehicle with a full FIA certified EV motorsport powertrain system and battery.

Electric Powertrain

The car is equipped with STARD´s in house developed EV powertrain system which is the world´s first powertrain kit optimised for customer motorsport resulting in an unchalenged performance/cost ratio.

The powertrain system has full FIA safety certification which makes the C3 ERX the world´first ever road car based EV race car with with FIA certification and just the 2nd ever motorsport powertrain to receive this pedigree besides Formula E.

Offering 450 kW of combined power and over 1000 Nm of torque, the performance of the car is breathtaking.

The main targets for the powertrain system were :

  • Safety: the STARD prepreg carbon fibre HV battery pack is situated within the safety cell of the car and can withstand 60G deceleration without damage.
  • Reliability: The STARDxBRUSA E-Motors and Inverters are optimised for rough motorsport and based on road car technology which results in a perfect reliability even in harshest conditions.
  • User friendliness: based on MoTeC electronic hardware with a STARD in house developed software package, the complete powertrain is extremely easy to handle for customers even without any engineer support.

Michael Sakowicz, STARD CEO: "Our powertrain system is as cost efficient, robust and easy to handle as no other system currently on the market. This is also influenced by the complete turnkey solution from one supplier, STARD, which results in all individual elements perfectly matching each other.

The transmission is a STARD proprietary EV specific motorsport solution with unchallenged flexibility. Adjustable differentials, two gears and ratio options from 4:1 up to 14:1 for both gears offer setups from rallycross to top speeds over 300 km/h records.

Chassis and ground connection

The C3 ERX shares its rolling chassis and suspension components with Citroën C3 Rally2. As a result, performance and grip is optimised on any possible surface : from tarmac over to mixed surfaces or pure gravel with a number of setup options available.

It also guarantees a perfect quality and spare parts supply based on the proven established Rally2 concept from Citroen Racing.

Options include setups for 15“, 16“, 17“ and 18“ wheels.


While the extensive development and racing activity of the Citroen C3 Rally2 chassis is well known, the STARD powertrain system has also undergone a huge amount of testing and racing activity by STARD and worldwide customers.

The Citroën C3 ERX's powertrain has completed around 10.000 km of test and race distance since middle 2019, at the hands of over 60 professional independant race drivers.

The thorough testing also covered all types of surfaces - ranging from gravel, ice, snow, tarmac and mixed surfaces - and temperatures - ranging from -20°C to 38°C - proving the functionality of the system in a wide range of possible conditions.

At its international race debut in the Projekt E race in 2020 in Riga, Latvia, Cyril Raymond has driven the car to its first race victory at its first event.

Citroën Racing and STARD are continuously developing the car further.


The C3 ERX has been primarily developed for the FIA international series Projekt E, which was launched in 2020 as the leading electric support category in the FIA World Rallycross Championship.

However the car can be raced in a big number of international and national racing series worldwide, with additional series being added continuously.

ERX (former known as Projekt E)

DRX (German National Rallycross Championship)

BRX 5 Nations (British Rallycross Championship)

Austrian Rallycross Championship

Hungarian Rallycross Championship

Norwegian Rallycross Championship

Italian Rallycross Championship

Hillclimb Events, City Rallysprints, Rallysprint Events

If you plan to compete in a series which is not listed below, please contact STARD for support and advice.

Technical sheet

Model : STARD Citroen Racing C3 ERX

Vehicle : C3 Rally2 based, developed and built by STARD supported by Citroen Racing

Vehicle type : Electric Rally2 based AWD Race Car

Body : Citroën C3 Rally2 based bodyshell with FIA homologated rollcage

Bodywork : Citroën Racing C3 Rally2 based Carbon Fiber Bodywork

Performance :

Combined Power / Torque : 450 kW / 1002 Nm

Powertrain : STARD #REVelution RCR3b Motorsport EV Powertrain

E Motor : 3x STARDxBRUSA specific Motorsport Hybrid Snychronous Motors & Controllers

E-Motor Position : Transversely Mounted 1x Front and 2x Rear

VCU (Vehicle Congrol Unit) : Central Motec M150 VCU with STARD developed firmware

Power and Torque per Motor : 3 x 150kW / 334 Nm peak / 13.500 max rpm

Torque Distribution : STARD proprietary 2-Axle Torque Vectoring system

Battery pack (RESS) : FIA approved STARD #REVelution RESS-CR-0403-A01 Motorsport Battery Pack

Cells : STARD specific Ultra High Performance Li-ion cells

Minimum Charging Time 80% SOC : Fast DC-20 min, STD DC-56 min

Casing : FIA tested Carbon Fibre Structure with Quick Release Fixation

System Voltage / Capacity : 420 V / 35 kWh

Cooling/Heating : STARD proprietary Liquid Conditioning System

Electric / Electronic : FIA approved System and Safety Features

Wiring loom : STARD proprietary Motorsport Wiring Harness

Driver display / data logger : Motec C127 Display with Logging Function

Power distribution : Motec PDM30 Power Box with STARD Software

Transmission : STARD #REVelution 2-Motor 2-Speed Motorsport Transmission

Type : Up to 2 Motor Input (1 per side) with shared Input Shaft, 2-Speed and straight cut Gears

Position : Front 1 Transmission with 1 Motor (2nd Motor Option), Rear 1 Transmission with 2 Motors

Shifting System : Electric rotary Acutator with Dog Gears (paddle shift)

Differential : Multi-discs adjustable limited Slip Differential, external Preload adjustment

Layout : Independant Front & Rear axle, no mechanical connection Front-Rear, same Transmission Front & Rear

Suspension : Citroën C3 Rally2

Type : Citroën Racing Rally2 based Mc Pherson Front and Rear

Damper : Citroën Racing Rally2 based Reiger Dampers 3-way adjustable

Steering / Brake : Citroën Racing C3 Rally2

Steering : Citroën Racing Rally Electrohydraulic Steering System

Brake system : Citroën Racing Rally Alcon Brakes Front and Rear, blended adjustable Recuperation

Pedal box : Citroën Racing Rally Pedal Box with Brake Balance Adjuster and Rr Brake Pressure Reducer

Wheels : STARD OZ-Racing Magnesium Wheels


Length : 3,996 mm

Width : 1,830 mm

Wheelbase : 2,567 mm

Track Width : 1,640 mm