Charcoal Filters
 

Does anyone here know if the X5 4.8i engine has charcoal filters similar to the M5 that can be removed for simple upgrade in HP? The M5 has filters that when removed, can increase RWHP from about 15-20hp...

I've looked, but they seem to be non-existent. However, I've read that 550/650 owners have the charcoal filter, so maybe I just missed it.

I was wondering the same thing !! I believe that the 4.8i engine would gain at least 20 hp and thats due the twin air intake .

I'm not sure you want to do that... filters are there for a reason, no?

These charcoal filters exist in addition to the air filters....and are only present in North American spec cars due to emissions regulation. You won't find them in a Euro spec vehicle, so it won't do any harm taking them away.

are these filters you are talking about the ones for the air filter or cabin filter?

The filters that the post is referring to is the air filters and there is NO carbon filters. Do not, and I repeat DO NOT try to take the air filters out for more power because it will damage the motor. I know it sounds stupid but stupid is what stupid hears and ppl have made this mistake. I have taken them out on my M5 but thats a different story. Drop in filters are a really good mod, bang for the buck deal. Afe or K&N filters would be good for who is considering them. GL

Agree with toohotdoc. The filters being referred to are for evaporative emissions on the M5. When you shut down a hot engine, the fuel in the intake evaporates into the atmosphere. The charcoal filters are on the intake, in addition to the dust filters, and they capture and hold that vapour, releasing it into the engine intake when the engine is started again. They are not part of the cleaning system for the intake. They have minimal restriction, and I don't know why people refer to magical 20 hp gains when it is negligible.

jst2878, we are not talking about the cabin filters. Toohotdoc, we are NOT talking about the intake air filters either. I don't think anyone would take the actual air filters out for more power, that's just dumb if you run it everyday. The charcoal filters are fitted in addition to the intake air filters by BMW for certain North American spec motors which, as JCL correctly pointed out, is for filtering emissions that come out from the intake tract after the engine is shut off. These filters do not exist in European spec vehicles. I don't remember exactly what the gains were, but they are there, even if minimal. It's free, you get more power, absolutely NO harm is done, so why not? I personally haven't found them in the X5, however they do exist in the 4.8 motor in the 5 and the 6, so maybe I just missed it. So, can anyone confirm if we have these filters?

I have heard that on the M5 the gains are 10-15hp:wow: . I believe it, sure felt like it was more power when I removed them from my car.;)