RR

I have a few questions of the Sport Button and exhaust sound when pushed on the RS.

1. When the sport button is NOT engaged, the exhaust valve opens up anyways at I think 4500, or 5000 rpm, is this correct?

2. Also when the Sport button IS ENGAGED, is the exhaust valve ALWAYS OPEN, or do you need also a heavy throttle foot as well to open it.

Thanks,

R

John Boggiano

To the best of my knowledge -

1. About 4000, I think.

2. Yes and no, respectively - you can tell at idle.

RR

With the Sport button engaged mine didnt seem to be open at all times, its almost sounded like it opened up only with a heavy foot.

RR

Are you sure that it really is on all the time EVEN with the Sport Button engaged.
Here is parts of a thread that was started in May about the subject, I just wanted to find out more.
I don't think the Sport Button opens the muffler ALL the time, I think you still need a heavy foot. What do others feel?

05-23-2007, 01:29 AM #1
cladd
Addict
Rennlist Member


Join Date: Jun 2004
Posts: 185 I disconnected the plug to make the muffler loud and

--------------------------------------------------------------------------------

it is way lounder than when I used to use the sport button!! There was a noticable difference before when I hit the sport button, but it was more subtle than I thought it should be. Now with the electrical connector unplugged as shown in recent threads, it is crazy loud. Any possible explanations? Could ounly one muffler have been bypassed before??
__________________
Chris

cladd
View Public Profile
Send a private message to cladd
Send email to cladd
Find More Posts by cladd
Add cladd to Your Buddy List

05-23-2007, 02:16 AM #2
krC2S
User


Join Date: Jul 2005
Location: Boston, USA
Posts: 366

--------------------------------------------------------------------------------

that's the case with PSE optioned 997's because it stays closed at certain low/mid rpm range even with sport on while disconnecting makes it on at all rpms

this was the first thing i did but it still doesn't sound as good and loud as i hoped

Ran

In my opinion, the sound characteristics are certainly more robust with the sport button switched on EVEN when the car is idling. No throttle push is required. While certain about the above statement, I am also fairly convinced and will verify one of these days by reading the Service Intro book that the SPORT button signals the computer to change all of the "sportier" characteristics thus the exhaust backpressure is reduced, torque and power increased via sportier engine mapping, etc. Of course to actually experience ANY added power/torque one has to depress the throttle but the mapping in the ECU is triggered and the added volume in the sound is experienced without any throttle push. Now that is just my understanding and I hope to verify one of these days when time permits but I am 100% positive that the actual sound is substantially louder simply at idle.

RR

It is louder at idle, but it is not fully open throughout all the rpm ranges, even with the Sport button pressed.

NoSubEDU

Sport mode opens up the flaps at idle but they close once you get over 5mph. Then they stay closed until you reach about 4k RPMs. It seems like the GT3 is more rpm based on the exhaust flaps, whereas my C2S was speed based (would open back up around 48mph).

I remember reading somewhere it was based on European noise restrictions up to 50 kph.

95spiderman

+1

this muffler valve business is the only aspect of car i dont like. its more like playing a recording of exhaust sound than a true mechanical sound like my ferrari used to have. its quiet at idle then push button and gets louder only to quiet again until 4k rpm when loud again. stupid and annoying. should just be in loud position all time. its a sports car not a cruiser

also been pulled over by police several times b/c im trying to get valve open. luckily just warnings since i wasnt speeding but still.

RR

That is exactly my experience. Open at idle, closed at slow speeds, until 4000rpm, even with Sport button engaged.

R

pcar964

+1

It's a lot more satisfying listening to the older cars where the sounds are a result of the mechanical engineers, not sound engineers.

RR

Well it's not just Porsche that has that problem, Ferrari has the same thing.
Compare the 355 to the 360 or 430, they both sound horrible (IMO) compared to the 355.
I read somewhere its apparently Switzerland that has the strictest Sound Pollution Legislation, that's why all cars - not just Porsche's have been affected.

95spiderman

ferraris (and lambos to a lesser degree) still sound amazing compared to anything else, my gt3 included.

i was in monaco for a few days this month and there is a constant sound track of these cars that i never grew tired of. the italians do sound the best.

GelbGT3

The factory Service Information Technik brochure for the 997 GT3 states, in part, as follows:

"In the sports setting, the exhaust backpressure in the variable exhaust system is reduced, the gas cycle improved and the torque noticeably increased in the rpm range between approx. 3,000 and 4,200 rpm."

jsdkms

I am a little confused guys - Does the sport button modify anything other than the exhaust flaps? I have disconnected the connector for the exhaust vales but am wndering if the sport button also remaps the ECU like someone mentioned?

DrPeter

Yes it does