The Small Break Loss of Coolant Accident (SBLOCA) of a nuclear power plant is a transient that is subject to numerous studies. With the support of both experiments and simulation codes, professionals aimed to gain a deeper knowledge of the process, which would prove invaluable in the design and licensing of nuclear power plants. The comparison of integral test results with simulations serve as basis for licensing code validation. A notable example in its history of research is the series of IAEA Standard Problem Exercises (SPE), which were carried out in the 80s and 90s on the Hungarian PMK-2 facility, a scaled down model of the VVER-440/213 type pressurized water reactors of Paks NPP. This paper presents in detail our RELAP5, TRACE and APROS models that were recently developed for the simulation of the fourth Standard Problem Exercise (SPE-4). In order to assess the reliability and adequacy of these models, both qualitative and quantitative analyses were performed, for which the available measurement results served as reference. Quantitative analysis was performed using the original and the improved Fast Fourier Transform Based Method (FFTBM) and the Stochastic Approximation Ratio Based Method (SARBM). The application of these methods allowed for a thorough evaluation of our models and provided a basis of comparison with previously published results.