To go along with the CF front lip that I've already posted here, forum member "Mercedes Benz" also sent me a CF diffuser for trial installation. Removing the OEM plastic rear diffuser is pretty simple once you know how it goes together. I didn't take picture of that process, but it goes something like this;

1. Remove the (2) screws under the diffuser and drill out the small center rivet.
2. The OEM diffuser is actually (3) seperate pieces consisting of the main part and (2) trim pieces around the exhaust cut-outs. Remove the exhaust cut-outs by pushing them forward, toward the front of the car. It requires a little force, but the tabs will unlock.
3. Pull off the main part of the diffuser by pulling it straight off the car. Like the exhaust cut-outs, it requires some force, but the tabs will unlock and the diffuser comes right off.

I have to admit that I had a hard time fitting the CF diffuser on and actually gave up. I couldn't get the tabs to go in and apply enough force to lock them in place. The main reason for this is you have no access to the back of the bumper cover to push the other way. Frustrated, I re-installed the OEM part and went for a few beers to clear my head.

I decided to try again this morning but this time I'd remove the rear bumper cover completely to allow access to the back side. I'm a decent wrench, but the thought of taking my new Porsche apart was a little overwhelming. Once underway, I was amazed at how easy and simple the cover came off and went back together. For those of you sweating the air filter change, don't worry! I attempted to document the process with pictures below. So here goes.

1. Remove the fans as a unit by pulling up on the rear most section to unlock the (2) vertical tabs and then pull the whole assembly toward you to unlock the (4) front horizontal tabs. Now that I think about it, I'm not even sure this step is necessary.

2. Pop off the (2) covers hiding the tail lights screws.


3. Remove the screws holding the tail lights. There's (2) per side. The tail lights come right off.



4. There's a bigger torx screw on each side of the tail lights access. Remove them.


5. Remove all the smaller torx screws holding the cover. There's (3) in each wheel well, (2) under the cover behind each wheel facing up, (2) under the center and lastly (4) on top.



6. This is all the fasteners I removed. I know I took off some that were not needed such as the bigger ones highlighted.



7. There you have it, a naked rear end! I was able to remove the cover by myself with no trouble. Unplug a single connector and you're home free. There's a video on youtube from Freemont Porsche titled Deconstructing a 991 that was helpful. The tech shows the motions necessary to remove the cover. You basically just start wiggling it side-to-side and it comes right off.




8. Cover ready for CF diffuser marriage. I taped the cover to prevent any scratches or marring. OEM diffuser is already off.





Re-assembly is reverse and straight forward. I did get my wife to help me guide the cover back on to avoid any accidental scratches.

Back together with a little bling. I personally think it looks awesome. Contact "Mercedes Benz" for any and all product information.

 

Very nice!!!!!

 

Where to buy these items? Front and rear???

 

This post is very useful. Thanks for the pics and info.

 

I'mAllIn:
Nice post! Do I understand that you can get to the bolts in the wheel well without taking the rear wheels off?

ChuckJ

 

Yes, although its tight. It was worse for me with a lowered car.

 

great post! It will help when I get my lift installed...

 

Nice

 

looks great. thanks


you just reminded me about the air filters. What a PITA!

 

Looks great and excellent tutorial

 

Many thanks for posting this. I did mine today and it went very smoothly because of your help.

 

Glad it helped. Great color combo on your car!

 

Thanks for posting, saw the same video but have not had a reason to remove the back end. This post will help when it's time.. Many thanks..

 

Thanks for this post. I am thinking of putting clear tail nlights on my TTS when they become available, and your tail light removal info is valuable.

 

Great write up! Tks for sharing!