Mine is a '06 955 Turbo. That picture in #101 is a bit unclear, seems to me like the curved pipe is on the outside of the muffler, that's not the problem I'm having. I'll have to get back to this when I get a chance to go under the car.

 

Hmm, strange. And its the stock exhaust?
Ill take a pic of mine, replacing the flex pipe this weekend with the straight stainless pipe.
mine does have a bend in it, but its about 19" in towards the center of the muffler, were the pipe heads back and out the muffler through the pipe towards the front, both sides do this. That is, the turbo muffler internal piping doesnt run all the way through from left outlet to the right to the muffler inlets,,like the Cayenne S. The flow in the muffler is separated.

 

Ok, so I originally did this mod in Sep 2018 to my 05 CTTwith 2.25" flex pipe, non stainless. To be honest i don't know how long the flex pipe lasted, but a month ago i notice thin slices of the flex pipe coming out my passenger tips. Soundwise i thought i just got used to the louder sound, when in reality it was getting quieter cause the flex pipe was falling apart.
so the pass side tips were plugged up and there were some remains of the flex pipe in the muffler onb that side,,see the pics. I used a vacuum and magnetic pick up to get everything out. Surprisingly, there wasnt much left. On cold mornings, i could see less exhaust coming out this side, cause it was plugged up.
Checked the driver side, unbelievebly there was nothing left of the flex pipe, just some very fine metallic particles. I couldn't believe it, it all corroded and got blown out I suppose.
Replaced the flex with Stainless Works 2.25" OD 304 SS pipe, in 2ft length, cut to 18.25" long for both sides. Summit sells it around $30 a pipe. This pipe was also 0.049" thick, the thinnest you can typically get, so flow is maximized. The pipe fit perfect in my stock CTT muffler. Loose enough to get all the way in, and then tight just as its all the way in. Left 1/4" sticking out of the muffler to pull out if wanting to reverse it. See last pic.

What i notice a month ago in the passenger tips

What came out of the pass tips and muffler

Cleaned out, notice bend at end of pipe to the right, this is the turbo muffler, no connection to the driver side as in the S

New 2.25" OD SS pipe cut to 18.25", fits perfect and tight

Great sound is back, and this should last as long as the muffler now.
DONT waste your time with regular flex pipe, or any flex pipe, even stainless i think will unravel with the vibration in the exhaust.

 

Here is a photo with the 2" flex pipe installed on the right side muffler.




I used the 2" and it wasn't hard to insert once I gave the flex pipe a slight bend. On the left side you have the lil pipe protruding inwards that must be removed. I used a sawsall with a long blade. A lil piece was left intact so inserting the flex pipe on that side wasn't as easy. I slightly flattened the first six inches or so of beginning portion of the pipe with a mallet, inserted it while twisting and it went in. So no splitting. The hardest part was getting the tips off.

 

My 06 Cayenne S is just too quiet but I’ve wasted a bit of cash trying this mod already.

Two sets of pipe at £23 each only to realise that my exhaust is a little smaller in diameter here so need to order another but that’s on hold as the little pipe in the near side exhaust is proving problematic.

I’ve gone through three dremel cutting discs and two grinding stones as well as a hacksaw blade.

Anyone got a decent tip for removing the remainder of the pipe without resorting to my 12 bore?

 

I used a 36 tpi hacksaw blade when I did mine this summer. It took about 20 minutes.

Hacksaw blade is the way to go I think, it is flexible enough to follow the curve of the exhaust pipe, I just got one that had the most tpi which I think made it easier.

 

thank you, I’ll grab another one and give that a go. Might have a look at the reciprocating saws too

 

recip 12.4 seconds

 

I have no idea what that means, care to elaborate?

 

commence to complete with the recip

 

excellent. Sounds like I need to borrow one of those then.

ta

 

There seems to be a product already made for this purpose
https://cayennebypass.com/index.php

 

hi did you ever have a go at this on your 957? I'm wanting to give it a go. Just not sure how easy/hard its going to be to get the pipe in as there is a bend in the exhaust after muffler on the 957

 

How did you get the tips off? Did you have to remove the bumper?

 

They should just come off by twisting and rotating after releasing the clamps. Mine were rusted solid and crumbled off when removing them. Bumper doesn't need to be removed. I supported the exhaust with a jack, then took out the bolts holding exhaust hangers to body. Then lowered the exhaust slowly just enough to get access.