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The dealer sent the following that shows the algorithm of the flap operation with the following note:


"There is an algorithm that controls the flap. It takes into account what gear the transmission is in, engine rpm and air quantity the engine is ingesting. The attached chart shows all parameters for operation of standard exhaust and sport exhaust. "


And Attachment:
http://1drv.ms/1hf3r2u


I am still not able to follow on how to create conditions so I can actually witness this flap working as it is always open after I have been driving behind our Macan. If anyone can interpret and post back a sequence of steps on how to make the flap close, that would be great help to me.
So...it's always open above 2700RPM regardless of flow conditions. I don't see the point of doing this "flap mod" if that's the case. Who drives these cars under 3K RPM anyways?
 

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So...it's always open above 2700RPM regardless of flow conditions. I don't see the point of doing this "flap mod" if that's the case. Who drives these cars under 3K RPM anyways?
And it is always open at idle. SO yeah, waste of time and lots of scrapes on your hand to do it.
 

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What I find interesting is that Sport and Sport Plus have no direct effect on the logic. There is a secondary effect in that the RPM is higher so the valve will open, but that's it.
 

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So, if you pull the plug you will keep the valve open all the time and probably have some increase in volume while sacrificing some unknown amount of low end torque due to loss of back pressure.
If the valve was important to limit loss of low end torque due to loss of back pressure, wouldn't this be a concern to those making aftermarket exhaust systems that don't utilize the valve?
So...it's always open above 2700RPM regardless of flow conditions. I don't see the point of doing this "flap mod" if that's the case. Who drives these cars under 3K RPM anyways?
If disconnecting the wiring harness has been increasing the sound coming from the exhaust, something else must be happening based on what's been reported here re the actions of the valve itself unless I've been reading the posts on this thread wrong. It seems not only at start-up, but at all RPMs after, there is a definite increase in sound, some even reporting a drone that some find objectionable. So what else is happening?
 

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So...it's always open above 2700RPM regardless of flow conditions. I don't see the point of doing this "flap mod" if that's the case. Who drives these cars under 3K RPM anyways?
I don't understand your logic! The RPM almost always stays below 2700 during daily use even in Sportsmode unless you are trying to get a speeding ticket :eek::eek:
 

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I don't understand your logic! The RPM almost always stays below 2700 during daily use even in Sportsmode unless you are trying to get a speeding ticket :eek::eek:

Mash the gas dude ! Haaaa just kidding . I very rarely go above 3k rpm on my daily commutes. Then again, my commute involves a lot of sticky LA traffic .


Sent from AutoGuide.com Free App
 
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If you use manual shifting and leave it in 1st gear, you will always be over 3000 rpm. :-0
 
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I don't understand your logic! The RPM almost always stays below 2700 during daily use even in Sportsmode unless you are trying to get a speeding ticket :eek::eek:
My commute is 95% highway, and I rarely get stuck in traffic. If I do get stuck in traffic, it's only because people fail to merge/yield without causing traffic. Anyways, once you go past that, downshift and 5k+ RPM to enjoy your drive back home (or to work).

This is how I drive my Macan (proper warm-up is no brainer). If I was going to keep it under 3K RPM (I don't remember last time I did this), I wouldn't have gotten any performance options (and I probably would've picked up Honda CRV). I didn't buy it for others to enjoy how sexy my car is. >:D

Of course, please drive responsibly and don't be like Magnus Walker. ;)
 

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And it is always open at idle. SO yeah, waste of time and lots of scrapes on your hand to do it.
No, it is not, at least not on mine. There was a pronounced difference with the sound at idle when I disconnected the plug.
 

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Another alternative to a bit more exhaust noise - put the rear seat down. It is virtually free, easily switchable, and works!
 

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If the valve was important to limit loss of low end torque due to loss of back pressure, wouldn't this be a concern to those making aftermarket exhaust systems that don't utilize the valve?

If disconnecting the wiring harness has been increasing the sound coming from the exhaust, something else must be happening based on what's been reported here re the actions of the valve itself unless I've been reading the posts on this thread wrong. It seems not only at start-up, but at all RPMs after, there is a definite increase in sound, some even reporting a drone that some find objectionable. So what else is happening?
So further to my previous post, does anyone have any insights? :confused:
 

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My suspicion is the exhaust flap has nothing to do with performance, and is there simply to alter the tone and keep the exhaust from developing a drone or buzz. Unlike many posting in this thread, I personally like the quietness of the car, and I preferred the way it was even quieter and smoother before the last software "upgrade". I kind of like the sound and feel of a limo with 400 lb-ft of torque pretty much instantly available whenever I want it.
 

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No, it is not, at least not on mine. There was a pronounced difference with the sound at idle when I disconnected the plug.
Porsche's own data https://onedrive.live.com/view.aspx...file,pdf&app=WordPdf&authkey=!ABzS0vGH0_xNvJ4, and my visual inspection both show the flap open at idle (for a non-PSE system). Don't know what else I can say ? I only detect a suble difference while driving between it plugged and unplugged.

All the PSE systems I know of are known to close their dual flaps off-idle up to 3000 rpm or so (depending on load). This is a noise suppression issue in the EU. A common solution on the B/C/911 is to wire a switch in series with the line that controls the vacuum solenoid. That prevents the DME from closing the valve in that all important low range when you are accelerating. I have such a switch in my Spyder. I can be civil when I leave in the morning and then open it up at the first light.

On the Macan, the valves are electrically operated, so disconnecting the connector should do the same thing.
 

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Another alternative to a bit more exhaust noise - put the rear seat down. It is virtually free, easily switchable, and works!
Yeah I had to take the luggage compartment cover off to haul some stuff and noticed more/better exhaust sound with that off. Folding the seats down is the obvious next step.

One insane/random question I have is this: how loud would it be if one took off one of the mufflers entirely? Like, insane loud?
 

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Yeah I had to take the luggage compartment cover off to haul some stuff and noticed more/better exhaust sound with that off. Folding the seats down is the obvious next step.

One insane/random question I have is this: how loud would it be if one took off one of the mufflers entirely? Like, insane loud?
Insanely loud. Did that back in the day on my mustang GT (custom pipes welded in place, my friend did the same but put resonators in place) sounded awesome (V8 Mustangs shine when uncorked, many engines won't), loud but surprisingly smoother than catless Mustangs with mufflers, loss of back pressure so loss of torque, car ran rich so mpg got lower (not sure if those things would happen as much on a modern Turbo?).

You could always have a shop try it out. Probably not too hard. Curious how it would sound. Could go either way.
 

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Looking at the algorithm, something tells me that the Porsche engineers, hired to improve performance and whose salaries we contribute to, wanted to make sure the valve was closed under low load. I'm speculating more and more that it was perhaps toward improving back pressure and potentially torque. The same is also apparent in PSE irrespective of whether the button is pressed or not. When the button is actuated, not all valves are completely open all the time either; that means something. The real proof of the pudding would be for someone to do a Dyno. One with the plug plugged in and one with the plug unplugged and let's see the difference.

I'll admit, the Macan sings when the RPM is above 2500 - that's when the valve opens. So, when I need the sporty feel and sound, the car's engineering does deliver what I need. I mean who drives a sport car - when in sporting spirit - at less than 2000 RPM? Nobody. But also, our life and environment don't allow us to be in sporting spirit all the time. Sometimes, you want to just sit back, cruise at 1800 RPM and listen to Bach. ;)
 

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For what it is worth, the Turbo I got didn't have the PSE and it doesn't make much of a noise from the inside on the car. I just disconnected the plug as suggested in this thread and will report back tomorrow.

Edit: Sorry for bringing up an old thread -- it was helpful for me.
 

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There is a subtle, subtle difference between having the plug disconnected vs plugged in. I personally do not find it worth it to have it unplugged; I'd hate for anything to happen to the plug from heat, if the zip tie comes undone, water/dirt/salt/whatever.

If you are truly wanting of a more prominent exhaust sound and this is your only option then in addition to disconnecting the plug: remove the items where the spare tire and kit are, remove the trunk compartment cover, and fold down the seats.

Personally, my plan is to drive a Macan Turbo with the PSE and purchase the system from Porsche if the difference is that worth it as I would like to hear more a bit more exhaust noise from inside the car.
 

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There is a subtle, subtle difference between having the plug disconnected vs plugged in. I personally do not find it worth it to have it unplugged; I'd hate for anything to happen to the plug from heat, if the zip tie comes undone, water/dirt/salt/whatever.

If you are truly wanting of a more prominent exhaust sound and this is your only option then in addition to disconnecting the plug: remove the items where the spare tire and kit are, remove the trunk compartment cover, and fold down the seats.

Personally, my plan is to drive a Macan Turbo with the PSE and purchase the system from Porsche if the difference is that worth it as I would like to hear more a bit more exhaust noise from inside the car.
I had my flap disconnected for a while but grew tired of the droning at highway speeds. It looks like they really did install it for a reason.
FWIW, my car just crossed 20k miles and the exhaust note in the car is much higher more prominent now than when it was new.
 
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