[JBH76]

I´ve not yet observed the left exhaust flap open on my 335i GT. I would like it to stay open permanently.

I followed the steps below for the 435i described in this thread:

http://f30.bimmerpost.com/forums/sho...hlight=exhaust

1) Set DHP settings back to Chassis and Drivetrain for Sport mode
2) Place the car in Sport Mode
3) Rev the engine in Park to about 4000-5000 RPM
4) Verify the left exhaust to be open
5) With the car on and left exhaust open, unclip the actuator on the left exhuast pipe
6) Secure the wire/clip and cover the actuator port to avoid and water/salt damage

…but the left exhaust doesn't seem to open at all !!

Any advise on how to active the motor for the flap (see pictures of closed left exhaust flap, motor for left flap and actuator)?






Thanks in advance !!

[Tameautumn]

Does this mode just impact on the exhaust sound, what about other knock on effects?

[Billfitz]

Originally Posted by Tameautumn

Does this mode just impact on the exhaust sound, what about other knock on effects?

It lowers back pressure when the engine is revving high enough to need it. That's why there's a louder exhaust note when you really punch it. At lower revs it wouldn't do anything useful, as there's not enough exhaust pressure to be restricted by its being closed. It would give a louder exhaust note all the time if left open all the time. It also would cause longer warm up time. IMO locking it open goes against the grain of the GT as the thinking man's BMW.

[n55x3]

You're not missing much. I wired mine open on my 335i and the drone was painful on long road trips. I rolled back the mod after only a day or 2.

Once you undo the clip on the flap you can move the flap by hand without issue. Then once you manually open it you have to wire it in place.

[JBH76]

Thanks a lot for prompt replies

It was simply to remove the clip from the flap motor (picture 2), open the flap and wire it in open position. Sounds better and easy to put the clip back if I want to drive 'the thinking man's BMW' some time in the future….