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newbie to the forum, likely take the plunge in next couple of weeks and change my carrera s for an rs4 saloon (kids getting too big for back of the porsche). noted in some of the threads that the valves in the exhaust close between 1,000-3,500 in sport mode, the porsche has same sytem with sports exhaust but its a simple matter of disconnetcing an electrical connector to have the flaps open the whole time. anyone know how they are activated on the rs4 and whether something similar is possible. on the 996 you could disconnect a vacuum hose in the engine bay and have same result.

They have vacuum hoses that operate them but not sure if the vacuum is generated indepenent of the engine.

The Sport button can be reprogrammed to activate the flaps so they stay open all the time in sport mode.

t_urbo wrote:
The Sport button can be reprogrammed to activate the flaps so they stay open all the time in sport mode.

Really?

Are you 100% sure?

More information on this please

Im having work done on the car this coming week and will report back straight after with the FACTS.

anyone know if the vacuum opens or closes the valves? on the porsche it closes them hence simply disconnecting the vacuum hose
or electric connection to the vacuum pump means valves are open the whole time.

cool

from what i know the vacumm is taken fron a union on the flexi hose from the airbox to the throttle body..its controlled by a solenoid and the vacumm is kept in a unit ready for when the S button is pressed so not to draw a load from the engine and ruin its performence..
its constantly topped up when the engine is running..

thanks, so presumably their is an overide to the solenoid between 1-3500 revs but if you can disconect the solenoid then valves will be open all the time or closed all the time?

The valves are at the rear of the exhaust held on by renewable clips, take one off and see?

I can't as I have a non-valved miltek!

Is it not worked the same as it was on the R32 Golf?

I thought the valve openned on "sport" and stayed open on sport, why only open between 1000 and 3500RPM?

its because of noise regs for new cars, they have to be able to travel at a certain speed at a max decibel level

there is a flexible pipe to each exaust from a unit located under the near side (I am talking about a RHD UK Avant) rear boot. If you lift this section of the flooring there is a unit which supplies the vacuum for the seats and exhaust. The vacuum opens the valve (for more noise) and tightens the seat bolsters.
colin

As soon as you turn the engine off the flaps open (the default position when engine is not running since there's no vacuum) irrespective of Sport button setting. When engine is started they automatically close until Sport button is activated.

The flaps can be overidden (disabled) by removing the plastic hoses attached to each vacuum actuator and then blocking the ends of the hoses off. The actuator is located beside each rear muffler. Details are in the body of this thread here:

http://www.audiforums.com/m_472175/tm.htm

Bottom line is great sound without engaging the Sport button

I've done this on mine and it works great. Hope this helps.