Boost is always going to be relative to the efficiency of each particular combo.
Take into consideration your cams (Auto cars l99 and stick cars ls3). Each car is going to respond a lilttle different. Now throw in a proper exhaust and air intake and everything changes again.
We've got a car here right now on 13lbs of boost making 800rwhp.
A few months back we shipped out a GTO on 91octane with 11lbs making 770rwhp.
Its all about efficiency of the entire combo.
If anyone needs pulley suggestions, feel free to give us a call.