Sport Exhaust

[stan]

I have a question on the operation of the sport exhaust. When you start the car the sport exhaust is defaulted on, and you may turn it off with the dash rocker switch. When you restart the car the sport exhaust is defaulted on again.

Now the question is can the system be reversed so you have to press the rocker to turn on the sport exhaust, or what would be the easiest way to have the sport exhaust off all the time (remove vacum lines)?

Also how does the system work.

Stan

2004 996 C2

6spd

[mffarrell]

There are many posts on this subject. I believe if you reverse the check valve, the operation will be reversed.

[stan]

I have searched with sport exhaust as the topic, but so far no luck. Does anyone have the electrical and vacum diagrams on the sport exhaust for a 2004 6 spd 996?

Thanks,

stan

[Loren]

Sorry can't remember who gave me this shot...

[stan]

Thanks Loren,

I did the search and come up with this simple solution that takes a manual approach. Let me know if I am wrong,

If you have the full system with the switch, to have the sport exhaust on all the time you would remove the air line at the solenoid that goes to both muffler air valves and plug the solenoid port. This cuts the vacuum to the air valves so the 35 mile cut off is also gone also. You need to plug the solenoid to prevent manifold vacuum loss.

If you remove both lines from the solenoid and connect them together you will supply vacuum to the air valves at all times and the muffler will be set in the quiet mode at all times. The problem is the dash switch will not do anything and if you want to change the setting, you have to reroute the vacuum lines which should take about 30 seconds.

You should buy female plugs and cover any open port to prevent dust from entering the system. Cost of this mod should be about a buck or two.

What do you think?

Edited March 15, 2005 by stan

[Loren]

Go for it. Let us know how it works.

[stan]

Well I did the mod and it turned out great. I can see now why everyone is doing the electrical mod on the 35 mile cut off of the sport mode.

To set the exhaust in the sport mode, you remove the vacuum line from the solenoid and plug the solenoid port with a female 5/32 plug to prevent manifold vacuum loss when the computer turns on the solenoid. Be sure to twist the hose to break the seal and be careful when you pull the hose off as the solenoid looks like it is plastic.

You can try this before you do the electrical mod to see if it makes a difference to you.

To set the exhaust in the quiet mode you would remove both lines from the solenoid and connect them together with a 5/32 straight fitting and plug both ports on the solenoid with 5/32 plugs to prevent dust from entering the valve.

I prefer this setting as I like the mechanical sound of the engine. I also noticed that when you drive around with the switch set in the quiet mode, the control valve solenoid gets very hot.

The problem with this set up is that your switch is bypassed and to change back takes a whopping 30 seconds.

If you have the sport exhaust without the electrical and vacuum set up you can run a vacuum line from the manifold to the mufflers, add a simple hand valve and have both modes available to you.

If you run lines to the muffler, I would pick up the stainless steel braided lines from Porsche or at a speed shop etc.

Stan

Edited March 16, 2005 by stan

[R1STCARRERA]

Well I did the mod and it turned out great. I can see now why everyone is doing the electrical mod on the 35 mile cut off of the sport mode.

  To set the exhaust in the sport mode, you remove the vacuum line from the solenoid and plug the solenoid port with a female 5/32 plug to prevent manifold vacuum loss when the computer turns on the solenoid. Be sure to twist the hose to break the seal and be careful when you pull the hose off as the solenoid looks like it is plastic.

  You can try this before you do the electrical mod to see if it makes a difference to you.

  To set the exhaust in the quiet mode you would remove both lines from the solenoid and connect them together with a 5/32 straight fitting and plug both ports on the solenoid with 5/32 plugs to prevent dust from entering the valve.

  I prefer this setting as I like the mechanical sound of the engine. I also noticed that when you drive around with the switch set in the quiet mode, the control valve solenoid gets very hot.

  The problem with this set up is that your switch is bypassed and to change back takes a whopping 30 seconds.

    If you have the sport exhaust without the electrical and vacuum set up you can run a vacuum line from the manifold to the mufflers, add a simple hand valve and have both modes available to you.

    If you run lines to the muffler, I would pick up the stainless steel braided lines from Porsche or at a speed shop etc.

  Stan

<{POST_SNAPBACK}>

Stan,

I am not an electrician so forgive my question if there is an obvious reason

why could"nt you just reverse the wiring on the switch at the dash?

JS

[stan]

The switch I believe is just a normal open contact and sets a relay to operate the sport exhaust valve. If it did work you would default to the quiet mode but at the 35 miles mark your sport exhaust would kick in. Hey that might not be to bad.

Stan