At 7 psi I think we were looking for close to double of what you posted..
" With a turbocharger or supercharger, it’s a different story. The induction system creates boost pressure to force more air into the engine. Turbocharging is one of the most effective ways to bolt on horsepower. You can bolt a turbo onto a relatively stock engine and produce as much power as you want by simple turning up the boost pressure. For every pound of boost pressure, a turbo can add up to 35 or more horsepower depending on engine displacement. "
Bolt-on Horsepower: Choosing An Induction System: Engine Builder