As great as it would be to use your logic, it is flawed. If the stock 4.6 makes ~17 hp per psi of atmoshere (260hp/14.7 psi), then you can say at 5psi, it may make 5*17 = 85hp more than stock...
Thats not my logic! Its yours. And I dont think we are going to agree on this, so I'm out.
Turbos make more power the superchargers at the same boost level because they dont have the parasitic power loss from the crank.