**4. Discussion**

The results of the experimental test of the engine with an additional expansion of exhaust gases are presented in this study. After the analysis, the author attempted to compare the obtained results mainly to that from [14], which shows the results obtained for a similar engine, but which was designed and built from scratch. Summary of the results of the comparison is as follows:


As a summary of this part of the work, Figure 16 shows the results of the above-described comparisons of these two engines, presented in graphical form.

**Figure 16.** Comparison of the best results obtained for the engine developed at CUT and that developed by Kéromnès et al.

Considering the obtained results, but also the indicated imperfections and limitations of the developed engine, the author plans for further development of the design. These activities will mostly cover:


pistons, since it is the only modification to the combustion chambers of the cylinders of additional expansion that is possible to make in the developed engine.

