[TupperBMW]

I wanted an opinion from people here: I have the Fi Exhaust for my M850i and the app lets you set when you want the valve to open and close.

In auto mode, I set the valve to open at 2000 RPMs. My thinking here is that I want the to decrease exhaust back pressure against the engine when it's being pushed. So I prefer to keep the RPM levels lower, more for the engine's safety.

Problem is, even on light acceleration I hit 2000 RPMs and I find the valve opening and closing frequently as it goes above and below that mark. Here are my questions:

1. Is wear and tear on these valves something to be concerned about?

2. Am I setting the RPM level too low at 2k RPM? Are my concerns about letting the engine "breathe" a bit unfounded?

Thanks

[Vic55]

1. Just leave the valves open
2. yes 2k rpms are way too low and see number 1.

If you have to keep the valves shut only because of neighbors, just start your car with them closed and then leave them open after you leave.

Too much thought sir into this I feel. On my M8 the valves are wide open all the time and so are the CS valves along with the GTS. The GTS was so damn loud at start up even with the valves shut that I had to code out the cold start; I dont think you will have that problem here with your cats still intact.

So just leave em open always as 2k is an irrelevant number and any one who drives their car will be over that threshold unless in reverse LOL.

[TupperBMW]

^ Great points. I actually do want to close the valves on certain days of the week when I start the car. Other than that, I keep it mostly open.

But......there is an Auto mode where I can have the valves set to close until you reach a certain RPM. There are times when I'm driving to or from work when I just get a bit tired of the valves being open (yes, there is a slight drone) and I'd like to be able to use Auto mode then. 2k RPM is looking too low. Maybe I'll give 2500 RPM a try

[Vic55]

Originally Posted by TupperBMW

^ Great points. I actually do want to close the valves on certain days of the week when I start the car. Other than that, I keep it mostly open.

But......there is an Auto mode where I can have the valves set to close until you reach a certain RPM. There are times when I'm driving to or from work when I just get a bit tired of the valves being open (yes, there is a slight drone) and I'd like to be able to use Auto mode then. 2k RPM is looking too low. Maybe I'll give 2500 RPM a try

The 992 has a sport exhaust button or basically a valve control but I found out that in reality they dont fully open until almost 5k and that clearly defeats the purpose of the flat six tt engine IMHO so I had it coded out 100 percent and dealt with a bit more exhaust noise down low.

I think some may call it drone but drone is such a subjective term/word and I rather enjoy hearing exhaust at all rpms. YMMV.

[bloozemanAZ]

Vic as always coming in with solid advice from years of experience. Mine only is even with stock exhaust and the valves open cold starts are loud as hell especially within the garage which helps "echo" them even more. I have solid relationships (minus one) with the neighbors in the houses surrounding me. For the one it's my little FU if they have an issue with it. The rest have all lived in the neighborhood nearly as long as I with me owning the house the longest (since 2002).

Not sure what your area is but here in AZ there are zero decibel limits for exhaust on anything under 4 tons. Literally only need a working muffler to "prevent excessive or unusual noise" (straight from the statute) so I'm golden. One of my neighbor's Harley blows the M850i out of the water so the "pesky" neighbor can go pound sand. 👍

[Broccoli-mobile]

I am also on team leave them open. If I were to program them to open on an RPM, I would have them open at 4000-4500 RPM. It would be high enough to not open in daily driving situations, but would open for "better breathing" when you get on it. Can def go down a rabbit hole considering everything with the valves

[bloozemanAZ]

Had an ironic conversation with the neighbor with the Harley (his weekend fun vs the Range Rover Sport DD and my absolute jealousy of his Aston Martin Vanquish). Asked him if he worries about firing up the Harley for his weekend drives with a MC he's in due to the pesky neighbor.

Answer "no" and he threw in I can hear your BMW when you come back from your weekend drives (my desert performance drives) as you rev in the garage on return. Yep, when I get back with the engine hot and exhaust hot I do a couple of 5K revs once in the garage just to relish in the absolute crack/pop/bang (no gurgles involved) before shutting down the car.

We both laughed as the "new kids on the block" complained about his remodeling dumpster on the street along with mine plus a porta potty as I had the crew with external access only to redo our MBR/bathroom, guest bathroom and my man cave home theater bathroom. While they did the MBR/bathroom and guest bathroom we lived in the guest room and used the man cave bathroom for our bathroom but the crew? Porta potty.

Both he and I won as we're not imbeciles so had everything approved by the POA. My parting words were fire that Harley up at 6am on the weekends even if you don't leave until 8am for the extra stick in the eye. 😜