You just need a turbo that can flow ~550HP worth of air at something approaching 30 psi. Plus exhaust, cooler, fuel pump, injectors, coils and management that can handle it. And an RB25DET gearbox. and a good clutch. And a proper LSD. And wider rear tyres than you can realistically fit on an R32. RB20s at that power level have nothing, nothing, nothing, nothing, ALL THE TORQUE....at about 5000rpm.