I know about the problem with running rich when you have the BOV vent into the atmosphere, and I was just wondering why you can’t put the MAF after the throttle. That way when you let off the gas or shift, you can have the BOV vent into the air and get the cool sound effect, and also have the correct air/fuel mixture.

So this is how it would be setup.

[engine]--[MAF]--[throttle]--[BOV]--[turbo]