15-20 psi....definitely gonna need bottom end work, and dont bother with turblownetics, get an airresearch garrett or somethin..gonna need pistons and rods, fuel management, fuel pump and injectors for more fuel, still need to consider the manifold, intercooler, piping, blow off valve, so on so forth...best kind of turbo...your not really saying how much power you want to make, soooo.......