Are you using a draw thru, or blow thru setup? The BOV could make you bog out (run rich) if your MAF is setup before the turbo, and the BOV is not recirculating the charge back into the piping.
In other words, if it's draw thru, it's: filter - MAF - Turbo - piping - BOV - Throttle Body - Intake manifold, the BOV needs to have a hose hooked up to it, from the BOV to the pipe between the MAF and turbo.
If it's blow thru, it's: Filter - Turbo - Piping - BOV - MAF - Throttle Body - Intake Manifold.