Dude, assuming that we are all talking about a turbo with an internal wastegate(he said stock wastegate on a t25), if it has no boost controller attached to it, it will stay close untill the exhaust pressure overcomes the spring tension on the wastegate actuator and will then open the wategate. It willl not run open unless the actuator is disconnected from the wastegate. So what ever the spring tension is set at is the factory boost setting.