Exhaust Valve Mod Comparison Video - Dueling F80 M3s

[motex]

Done it, well, not exactly, took the car to a friends tire shop, and he did it for me in less than 1 minute both, took longer to cover the plugs........haven't test it yet in open road, the good thing is that now I get the "Sport-plus" deep sound driving in the city traffic in efficient mode without the hassle of sport mode

Update:
Cold start sound is like starting a race car....LOL.....love it!
As for the low RPM sound, also great even in efficient mode, I was wondering if using the car more time in efficient mode will show better gas mileage in city driving? I was used to have it in sport mode all the time just for the sound, now there is no need

[Black Gold]

Edit : got it

Advice - use pliers and squeeze and pull. Mine were really in there

[Kief]

Did mine yesterday and my plugs were also in there very tight!

I'm a bit torn over the sound--anyone else? I really like the deeper bass, but I'm out the door at 3:30am to go to the gym and it was embarrassingly loud upon cold start in the garage this morning and when leaving the gym. There is also the drone which I haven't decided whether I want to live with.

It's pretty sad when my wife's M Performance Exhaust on our F15 (X5) sounds so much better than my M4...

[Black Gold]

Seems like the drone is more of an issue with the dct cars than the manual ones.

I have no drone issues and love the sound

[gthal]

Originally Posted by KennyPowers

Seems like the drone is more of an issue with the dct cars than the manual ones.

I have no drone issues and love the sound

I think this is correct... I have some drone on the highway cruising in 7th. It's easy enough to drop it to 6th if I want and then it is much better. However, driving in auto mode with the DCT (which I never do) would likely result in drone when the gear was high relative to the speed of the car.

The only thing about this I don't love is how loud it is early AM when I'm heading to work. BMW really should put an on/off switch on the console so you can toggle between on, off and auto (like the AWRON gives you). That would make this perfect... stealth for early morning subdivision driving and loud all of the rest of the time.

[AMPowerJ]

Originally Posted by KennyPowers

Seems like the drone is more of an issue with the dct cars than the manual ones.

I have no drone issues and love the sound

+1

The only thing I'm wondering is there really a performance penalty that someone else mentioned somewhere? I seriously doubt this is the case, since once the car is warmed up I think in Sport+ mode the exhaust is wide open except maybe while cruising to reduce 'drone' but now I am questioning it everytime I drive. But it sounds MUCH better for FREE so even if I lost a 1/10 in the quarter mile I'm not sure I would care.

[AMPowerJ]

Originally Posted by gthal

The only thing about this I don't love is how loud it is early AM when I'm heading to work. BMW really should put an on/off switch on the console so you can toggle between on, off and auto (like the AWRON gives you). That would make this perfect... stealth for early morning subdivision driving and loud all of the rest of the time.

It is still not exactly quiet on cold start in the morning with the valves closed. It just sounds like you are getting ready to do yard work way to early in the AM.

[gthal]

Originally Posted by AMPowerJ

+1

The only thing I'm wondering is there really a performance penalty that someone else mentioned somewhere? I seriously doubt this is the case, since once the car is warmed up I think in Sport+ mode the exhaust is wide open except maybe while cruising to reduce 'drone' but now I am questioning it everytime I drive. But it sounds MUCH better for FREE so even if I lost a 1/10 in the quarter mile I'm not sure I would care.

I think the valves are closed somewhat even in lower gears at lower RPM in Sport+. I only think this because the car is louder and deeper from 1,500 to 3,000 RPM in all gears when the valves are disconnected than even in Sport+ in my opinion. Hence why driving away in the early morning is louder

That could be why there is a perceived drop in low end power. So, IMO, the valves are in play during highway cruising and low RPM situations even in Sport+. From 3,000 +/- RPM to redline, I think it is the same between disconnecting the valves and sport+.

[Kief]

Originally Posted by AMPowerJ

It is still not exactly quiet on cold start in the morning with the valves closed. It just sounds like you are getting ready to do yard work way to early in the AM.

:
Yeah, yard work at 3:30AM!

[Accel Junky]

As far as drone, in my 6MT I notice none. In fact the car is still absurdly quiet (for my taste).

As far as performance effects, I cannot tell a difference between the low RPM spooling in my M3 vs my wife's. I'll get some more videos up soon.

Cold starts are really loud. I'm lucky my neighbor facing my garage has a double lot so their windows are a good 40 yards away. No complaints yet but I would not be surprised if they come soon.

I think we didn't get invited to the neighborhood Christmas party though...

[CanAutM3]

Originally Posted by gthal

BMW really should put an on/off switch on the console so you can toggle between on, off and auto (like the AWRON gives you). That would make this perfect... stealth for early morning subdivision driving and loud all of the rest of the time.

I have though about this too. I would change the valve control logic as follows:

Efficient: Always closed. I find it quite annoying when I press on it to do a quick stealthy pass in urban areas and when the engine gets at 4000rpm I get that loud BWAAAARP!!!! .

Sport: Mostly open but varying opening and closing depending on driving conditions, exactly as it is now .

Sport+: Always open

[Kief]

Originally Posted by gthal

I think this is correct... I have some drone on the highway cruising in 7th. It's easy enough to drop it to 6th if I want and then it is much better. However, driving in auto mode with the DCT (which I never do) would likely result in drone when the gear was high relative to the speed of the car.

The only thing about this I don't love is how loud it is early AM when I'm heading to work. BMW really should put an on/off switch on the console so you can toggle between on, off and auto (like the AWRON gives you). That would make this perfect... stealth for early morning subdivision driving and loud all of the rest of the time.

In the morning, does it quiet down a bit if you let it warm up a few minutes?
It was so loud this morning I was in a rush to get out of my garage/driveway!

[gthal]

Originally Posted by Accel Junky

I think we didn't get invited to the neighborhood Christmas party though...

[nasdaq100]

Originally Posted by AMPowerJ

+1

The only thing I'm wondering is there really a performance penalty that someone else mentioned somewhere? I seriously doubt this is the case, since once the car is warmed up I think in Sport+ mode the exhaust is wide open except maybe while cruising to reduce 'drone' but now I am questioning it everytime I drive. But it sounds MUCH better for FREE so even if I lost a 1/10 in the quarter mile I'm not sure I would care.

I have no explanation about the performance. I didn't feel it either, just my VBOX show some better results with the plugs connected. I have tried many many times to make sure and the result was always the same. I end up to let them plugged because I drive most of the time in sport so the differences are not that noticeable expect in 4th gear and up when the valves remains closed. I did 900 km on a highway with the valves opened and an Advil was necessary

[gthal]

Originally Posted by Kief

In the morning, does it quiet down a bit if you let it warm up a few minutes?
It was so loud this morning I was in a rush to get out of my garage/driveway!

I don't know... I'm always rushing to leave my street fast

[CanAutM3]

Originally Posted by nasdaq100

I have no explanation about the performance. I didn't feel it either, just my VBOX show some better results with the plugs connected. I have tried many many times to make sure and the result was always the same. I end up to let them plugged because I drive most of the time in sport so the differences are not that noticeable expect in 4th gear and up when the valves remains closed. I did 900 km on a highway with the valves opened and an Advil was necessary

That is very interresting. I wonder what would explain this from a technical perspective...

[motex]

I'm doing a full tank test in efficient mode just to check if Gas mileage shows any difference

[nasdaq100]

Originally Posted by CanAutM3

That is very interresting. I wonder what would explain this from a technical perspective...

I would like to know as well, I thought about back pressure but it doesn't make sense because this is a turbo car. If the car turned to a saving mode due to an error the car would be really slower not just a few tenths of second... so I really have no idea.

[motex]

I used to drive the car in sport mode all the time just for the sound, now that sounds great on efficient mode I thought there was no need to use sport mode in city driving, just remember I have my start stop feature off at all times, coded by the dealer

[Rusk]

This might be one of the first mods I think about when I pick my M4 up this week!

[X2Board]

My car hating, a-hole, neighbor across the street is in for a rude awakening. I usually back into my garage, but Blau will be parked nose in when she gets here. I have to listen to their neglected dogs bark for hours on end every single day!

[smedin]

Originally Posted by CanAutM3

I have though about this too. I would change the valve control logic as follows:

Efficient: Always closed. I find it quite annoying when I press on it to do a quick stealthy pass in urban areas and when the engine gets at 4000rpm I get that loud BWAAAARP!!!! .

Sport: Mostly open but varying opening and closing depending on driving conditions, exactly as it is now .

Sport+: Always open

YES.