You want your Wastegates to limit boost. So in other words, at a certain boost level, you bypass exhaust going thru the turbine. That will limit the air put out by the turbo. By trying to do it with a BOV, the turbo is making whatever air it can and you vent that air out the intake. The wastegate is way more direct and controllable.
What is your wastegate setup? If you have internal wastegates, they may be doing the limiting anyway.
97 Laser Red GT-248A Wingless model, Built Lincoln Mark VIII motor-Procharger D1SC, 3 core IC
2012 Black GT-Saddle, 3.73s, Brembos, Shaker1000