PorscheDoc

I don't know if anyone has done this or not for you guys, but I installed a set of secondary cat bypasses and catback exhaust yesterday on a Cayenne S, and figured I would shoot some pictures of the install:

http://www.turbo911.com/showthread.php?t=305

Kooser

Great post. This is what the forum is all about. It will assist many future users to come. Thanx

NelsonF

Great info and nice job, Stephen. I think I'll check out the cat bypass pipes. Now, if only GIAC would update their s/w upgrade for the Turbo to accomodate my new Turbo S.

User 4221

Yep.... It will assist me tonight as I bolt in the cat bypass pipes.

Thanks for the write-up!

Stone43

Wow, great post. I almost thought I mistakenly landed on a 911 forum (I used to spend way too much time on that one).

I had my cat bypass pipes installed around 4 months ago. I like them but do not love them. I am still trying to get used to that "metallic" sound when you first step on it and the engine is ramping up RPM's. I can see where the muffler will truly complete the job, but I just have not been able to justify the extra expense (yet).

I could not believe the size difference between the mufflers in your pictures.

Excellent job, as I am sure this will be referred to a lot since this is such a popular upgrade.

PorscheDoc

I have done quite a few secondary cat bypass pipes on V8 touaregs, without doing the muffler, and I agree, I think to maximize the sound and get rid of the metallic sound, you really need to do the muffler as well. I think the metallic sound is a little worse on the Touaregs, I don't know if that is because of the different intakes or not. On the cayenne with the muffler, the sound is very throaty, but when driving, it isn't over powering like some mufflers are on 911's. Standing behind the rig though, you know it means business I was quite shocked at the size difference as well. Even with it laying the ground, it was a beast to turn over.

Cognac

Great post!!!
Any air filters by any chance?

Gert

Hi Stephen,

You can loosen that difficult #3 nut of the passenger side cat by using a very long extention on the ratchet. Open the hood and you can reach it via the right side of the engine.

PorscheDoc

Yup, a really long extension and you can get it from up top as well. I have the curved wrenches, just usually do it from underneath.

Karl

Budget M3

I expect to install my bypass as soon as it arrives in the mail. Since I did not have either tool, I searched Sears and a few local specialty tool shops for the curved wrenches--not an easy tool to find! Where did you get yours, Doc? Alternatively, how long does the ratchet extension need to be?

Thanks!

PorscheDoc

Mine are actually snap on, but sears should have half moon wrenches, that is a bit odd that they wouldn't. Lol, to get it with an extension, you are going to need a couple of feet easily.

Budget M3

Thx, Doc...Sears now only carries exactly ONE half moon wrench in the current parts catalog, and it's an SAE size to boot...looks like I'll be buying that 2+ foot extension....

Raptor

Doc: Nice post. Good detail. Thanks.