We present results of several numerical studies with Wilson fermions relevant for kaon physics. We compute the BK parameter by using two different methods and extrapolate to the continuum limit. Our preliminary result is BKmaMS(2 GeV) = 0.66(7). ΔI = 3/2 K → ππ matrix elements (MEs) are obtained by using the next-to-leading order (NLO) expressions derived in chiral perturbation theory (ChPT) in which the low energy constants (LECs) are determined by the lattice results computed at unphysical kinematics. From the simulation at β=6.0 our (preliminary) results read: 〈ππ O7̄MS(2 GeV) K〉I=2=0.14(1)(1) GeV3 and 〈ππ O8̄MS(2 GeV) K〉I=2=0.69(6)(6) GeV3.