when i had my car running my BOV made a wierd sound when it blew off....it like a fluttering sound like a cat purring...??

I have only one of the vaccum lines ran and its the one closer to the top....any thoughts?

 

how much boost are you running? im not too up on the greddy's but i do know companies such as tial will only function properly if the correct spring is in the unit

 

play with the adjusting screw at the top.