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Chiptuning and mass conversion approval — when a power change is legal

Verified 23 June 2026 · RoadLegal.cz editorial team

The Czech Ministry of Transport approves mass conversions of road vehicles that change engine power and torque output. If the modification is carried out by a company holding a valid mass-conversion decision (HP), it complies with the regulations and doesn't change the vehicle's roadworthiness status.

Who can legally perform chiptuning

A company authorized to carry out the relevant mass conversion may register the change in the vehicle's documents and fit the vehicle with a plate stating the approved engine modification. Based on this registration, the relevant authority can update the vehicle's records.

Current holders of a mass-conversion decision for engine power/torque include, among others:

CompanyCompany IDConversion No.
Hošek Motor a.s.63484463HP-0287
Legální Chiptuning s.r.o.05235634HP-0288
PowerTEC - značkový chiptuning s.r.o.01533461HP-0285
XTUNING LTD. - branch03933687HP-0296
Volvo Car Czech Republic s.r.o.63981726HP-0163
M Motors CZ, s.r.o.27192636HP-0200
Profichip s.r.o.28354699HP-0436

What's illegal

Any other engine modification not carried out with the manufacturer's consent, by a mass-conversion decision holder, or registered with the relevant authority, counts as an unapproved change to the vehicle's type approval — resulting in loss of roadworthiness status.

Legal basis
  • Act No. 56/2001 Coll., on the conditions of vehicle operation on roads
  • Decree No. 341/2014 Coll.
  • Ministry of Transport decision on mass conversion (HP)
Required paperwork
  • The change carried out by a company holding a valid mass-conversion decision (HP registration number)
  • The change recorded in the vehicle documents by that company
  • A plate on the vehicle stating the approved engine modification
Authority
ORP transport department (based on the registration made by the authorized company)
Inspection/verification
STK