Preprocessing techniques are crucial for SAT solvers when it comes to reaching state-of-the-art performance as it was shown by the results of the last SAT Competitions. Theusefulness of a preprocessing technique depends highly on its own parameters, on the in-stances on which it is applied and on the used solver. In this paper we first give an extendedanalysis of the performance gain reached by using different preprocessing techniques in-dividually in combination with CDCL solvers on application instances and SLS solverson crafted instances. Further, we provide an analysis of combinations of preprocessingtechniques by means of automated algorithm configuration, where we search for optimalpreprocessor configurations for different scenarios. Our results show that the performanceof CDCL and especially of SLS solvers can be further improved when using appropriatepreprocessor configurations. The solvers augmented with the best found preprocessingconfigurations outperform the original solvers on the instances from the SAT Challenge2012, achieving new state-of-the-art results.