Mr nizmo4 I agree most people put them for the sound! ( If I wanted the CHsssshhh! sound I would open a bottle of coke! lol!
I however do prefer the flutter you get without the BOV!)
There is a bit of again you get by haveing a BOV and that is the when you release the throtle for gear changes the excess presure is released and the turbo is still kept spinning so as it with still be creating boost for when the throtle in pressed again!( If you change gear quick enough you wont even notice this even if you dont have a BOV)

I personally feel that it is better without a BOV as when you change gear with a BOV you still have the same boost and this power is going straight on the gearbox! ( Leading to breakage!)

I see it to be a win, win, No win situation!


And like I said and others have said and repeated a low pressure fuel pump it no good! ( You need a hi pressure fuel pump off of an EFI car!)