Three dimensional particle in cell simulations are used for studying proton driven plasma wake-field acceleration that uses a high-energy proton bunch to drive a plasma wake-field for electron beam acceleration. A new parameter regime was found which generates essentially constant electric field that is three orders magnitudes larger than that of AWAKE design, i.e. of the order of $2 times 10^{3}$ GV/m. This is achieved in the the extreme blowout regime, when number density of the driving proton bunch exceeds plasma electron number density 100 times.