Hey guys my gf just picked up an 07 MCS this weekend and she wants to have the BOV sound like one of my old boosted BMW's had.

I've been reading about this and I seem to get conflicting explanations and incomplete descriptions so I'm hoping someone can set me straight.

Apparently there is a "noise maker" that was installed that leaks boost and is only to make it sound to the driver that there is something special going on under the hood. I want to eliminate this, and at the same time put in something to give her this sound.

Can someone please tell me what options are available for this, such as the Forge BOV adapter, Alta boost tubes (or) Forge resonator tube, etc.

I'm also trying to get clear on how this system works with the diverter valve, does it remain?

 

buy an intake filter and the factory bypass is loud itself. BOV will be pretty pointless at factory boost levels.

 

A simple K&N air filter will make her happy. There are ways around paying top dollar, while still getting decent performance with a K&N. If you have any experience in an engine bay, you can rig something up yourself that works pretty well. Right off the bat you will notice a difference in throttle response, and it is especially amplified when sport mode is on.

On almost all boosted cars, switching from a closed intake to an open air intake will yield throttle response and a lot of great noises. You will be able to hear spool/vacuum and blow off A LOT.

Like Bigprfed22 said, a BOV is pointless at stock boost levels. Boost tubes can be changed, but like the BOV, they are kind of pointless at stock boost.

 

Also, if you want to remove the noise maker, go for it. There is no harm, it's not connected to vacuum. A PVC cap works well for plugging up the remaining hole.

 

I used the nm pipes and before my tune gained about 1 - 1.5 lbs of boost.

 

Really? Wow, I didn't realize the stock piping expanded so much!

BMW sometimes

 

Thanks for the reply's. I'm purchasing her the ddm kit with the functional hood scoop, and a long list of other stuff. It's only been sitting in my garage for a day and I want to pull the motor and tear it down, but i have to refrain and remember its not my car.


I'm coming from the old skool BMW scene so this is a nice change for me and gives us something to do together.

 

The gauge i had was a basic mechanical i had left over from an old project and wasnt zero'd but the difference was all that mattered. You have to think of it as air that is wasted "filling that space"

 

With a tune... say bye bye m3 (e46) not that big dawg lol

 

I just saw some youtube videos of the forge BOV adapter, and to be honest, that sounds pretty sorry, and nothing like my HKS used to.

I think I am going to go with the Alta pipes though, I've read that this pipe stock expands and creates a bottle neck. So I should at least give that a shot.

I'll look into plugging or using an alternate pipe. What is the fix you guys do for this?

 

hks ssqv works both of spring pressure and vacuum/boost. most bovs are by spring pressure which only makes them good in high boost situations.


Yeah altas are a good budget pipe but nm is where the quality is. Silicone heatsoaks more than aluminium

 

Oh cool, thanks for clarifying, I didn't realize the NM pipes were mandrel bent aluminum.

Do you guys also recommend their charge pipe for the IC to TB?

 

i have both... kinda pricey but quality of the couplers bands and pipe is superb.