Quote:
Originally Posted by BigJack75
So what is the secret to get the exhaust valve to stay open on f36 models?
|
From what I've read and seen... N55 equipped F36 GC and F34 GT exhaust valves under stock programming are set to open differently than other F3x models. The valve doesn't automatically open when switching to Sport(+), neither does it open while parked and revving high. The car HAS to be in gear and it will only open past ~2.7k RPM. My personal theory is this is due to these two models having hatches instead of trunks. Having the valve open at lower RPMs certainly causes unwanted resonance/drone and it will always be more audible through the hatch than a closed off trunk.
I experienced this with both the stock exhaust and MPE and also with or without MPPK flash on my 335i GT. I was able to keep the valve open all the time initially by twist tying the clip (crude but effective). Then I got the Bimmer Link app which has the option to open/ close flap on demand. But discovered that you have to open and connect the app everytime you restart the car, otherwise it reverts to stock settings. I started disliking the drone around 1.8k RPM, which is pretty much where you're at when cruising on the highway (8th gear). I also find the burbles at decelartion are more noticeable when the car is left to stock programming. So I just put it on 'Auto' under Bimmer Link which is basically stock and have left it at that.
I should add that I do have resonator delete and MPE w/ MPPK.