its all in the state of tune that is going to decide the maximum amount of boost. nobody is saying that you cant run 25 or 50 lbs of boost... but the engine will fail at those levels if the tune, does not match. this applies to ALL engines.
17 to 18 lbs is the SAFE limit to the amount of boost with nuthing more than just pump in the tank. with the proper tune and better gas, higher boost can be achieved.
But boost pressure is not a realative number,
just because another car has higher boost dosent mean mean that it makes more power..... that particular design of an engine or its tune allows it to run more boost pressure simple as that. comparing boost pressure alone to different engines is like comparing apples and oranges.
so yes, you can crank on the adjuster on the actuator , or add a bleeder and you will get more boost.... but if there isnt enough octane in the gas,or too much timing in the tune, poor adjustment, the engine will DESTROY ITSELF VERY VERY QUICKLY.
does this help?
A.j.