Currently discussed changes in the automotive sector, which are aimed at significantly reducing emissions of harmful substances in road transport, also affect the directions of development of motorsport. One of them is the use of electric drive systems. Currently produced electric cars are not technically prepared to compete in car rallies, both due to their performance and safety reasons. For this reason, rallies still use combustion engines and attempts are made to implement hybrid drive systems. Bearing in mind the above-mentioned limitations of electric drive technology, combustion engines will remain in car rallies for a longer time. Taking the above into account, the article focuses on the issues of exhaust gas treatment systems in rally cars. Tests were carried out to determine exhaust emissions from a car using a catalytic converter approved according to FIA guidelines and compare them to the current standards for mass-produced cars. Thanks to them, it was also possible to estimate the level of exhaust emissions on the approach sections of the car rally. A separate issue was the analysis of how much the use of an electrically driven compressor could reduce fuel consumption by limiting the operation of the ALS system, which is designed to maintain the turbocharger's rotational speed at a constant level. Reducing fuel consumption on the special stage would also have a positive impact on reducing emissions of harmful substances from the rally car.