OK I know I am not the first to do this, someone had to clue me in, but instead of plugging, crimping, or otherwise disconnecting the vacuum line under the car, just unplug the actuator in the trunk in front of the drivers side tail light. I was a little unclear as to how this works, but it's dead...

I also did notice a slight power loss of power at the low -to mid rpm range, but maybe its in my head, or maybe it was due to higher ambient temps, higher humidity (turbos not spooling as fast), etc. Not really sure what to think at this point. In the mean time, I have plugged it back in. Performance is more important to me personally that sound. But thats just my .02.

I think it's in your head. I don't see how the turbos will spool up slower if you have better exhaust output, meaning, both exhausts open vs just one. That just doesn't make sense. If you look at after market exhausts, they don't have the valve at all and have better output, they actually increase hose power slightly. Racecars just have straight pipes no valves. Check this out
http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=TEN9046MTP

http://www.turnermotorsport.com/html...ID=36TRACKPIPE

however just opening up the flap you will not see as much gain as the above. Maybe guessing 1 HP increase but the sound rocks, I love it.

so...is deleting this code possible thru the bav tech tool?

Did this over the weekend. Adds a nice amount of volume to the exhaust and no error codes. Thanks for the write up!

Be carefull with that, try concact your dealer before doing this, cos after this mod I felt loss of power, I think it's worth for sound only if u don't have moneys for real exhaust, just my opinion

Bad advice. Don't contact your dealer - they might void your warranty. Got any dyno charts to prove loss of power?

Well I red lot of reviews that after this zip tie u can get catalyst problems just try google it and u will see

Just did it, getting ready to leave work and see how it sounds!

Okay we wait for your post

ive seen it b4! i guess the basis of this is still disabling the butterfly valve..i guess my 07 never came with em..exhaust out of both pipes

Hi u want to say that 2007 year cars doesn't has that 2008 cars has?

yeah in a sense, some early production were not equipped it

I did it I noticed a more of Roar when starting car, but IMO when I'm driving I didn't notice a difference but maybe like everyone else say it's gets better over time I'll maybe notice a differnece sometime soon.

no. my nov/06 335 sedan had this mod

So it means that all 335i has that buterfly valve

does it sound better overtime? i hv the lci 335i, doesnt make much of a difference

Hi guys. I am going to put the cable back. Had my car in neutral yesterday at the traffic light, AC was on and Engine went off. Had the good sound for 2 weeks, but it is not worth loosing horsepowers and maybe money for gas.

HAHA, are you serious? No way was the exhaust flap mod a cause of this. There is no horsepower lost, if anything you actually might gain a tiny amount because of the reduced back pressure at all RPM.

+1

My bimmer sounds louder now after over 2 weeks of driving with the valve open, I guess the left side of the exhaust has to break in a little if the valve was mostly closed before. It sounds the best when driving in a tunnel as the noise get amplified. Here is my bimmer and stock exhaust sound 800 - 3000 rpm rev. It also sounds much deeper when you are driving since the engine has to work harder.

http://www.youtube.com/watch?v=UXl-Ax5j0b8

why would the engine have to work harder? if you reduce the exhaust restriction, what do you think happens to the engine?

This thread needs to be locked. this all has nothing to do with the DIY