im putting a blitz BOV and i welded the flange to the greddy FMIC piping...what do i need to block off when i run this...do i take the stock one off and plug the hole?...what about the popoff valve or whatever thats called?...any help

 

Are you still running the stock twins?

 

The other valve on the rear turbo air out pipe is the prespool vent and is needed ithe system is still sequential . If NON SEQ then open the butterfly valve or remove it and remove the prespool valve and plug the holes . Remove the stock blowoff valve and plug the hole . I weld the holes and smooth it all out .

 

im running the seq twins...

 

Technically, you could just leave them on and hooked up. Your aftermarket BOV would still work, since it's closer to the intake. You do need to keep the rear one, which is called the Charge Control Valve.