Porsche 991 Underbody Panels...
Needed to gain access to the area just above the underbody panels on my 911 front end (don't ask me why!) yesterday, and thought I'd share with y'all my experience. First, if you may ever have a similar need, know that the procedure is really quite simple! If you were to flip a 911 over onto its' roof, you'd find that the underside or "belly" of the 911 is almost entirely covered by smooth black panels. You would see very little of any mechanical bits at all the entire length of the car, with just a few glimpses near the far rear and nose of the car. The panels have been included on 911's for some years now, with the objective being more aerodynamics than anything else. Most that I've seen have channels and other features to smooth air movement under the car at speed. Panels such as these are common on supercars and race cars.
The purpose is to enhance the aerodynamics of the car at especially higher speeds. I was only interested in the Front panel, labeled "1" in the PET diagram. From what I can tell all of the panels are secured to the car in the same way, and in certain spots overlap. So the experience I share here of removing the front panel should apply for the other panels as well! On the front panel, the diagram above indicates fastener locations - If I recall correctly there are 10 Torx screws and 2 11mm nuts holding the panel up to the car. First, I ran the front of the car up on my Rhino Ramps. If you can get the car up higher, great. You will need to reach a number of fasteners to release the panel, and on ramps I found the maneuvering space to be tighter than I would have liked. I also blocked the wheels once the car was on the ramps, and also put a jack stand on the sides just in case the car moved while I was underneath.
I took the shot while lying on the ground under the nose of the car, looking to the rear. My first impression was "wow." For being on the underside of a daily driver, in the NE where we get all sorts of poor weather and road conditions, I was surprised by how these panels looked. The material is some type of "felt" over pressed board, or maybe even some kind of plastic. Very rigid, stiff, but feels to me like felt paper used in roofing or laying floors. No stains of any kind, and just a couple of very small marks from objects deflecting off the surface. The only visible sign of use was the dirt stuck to the surface, and road grit. I tapped on the middle of the front panel, and could hear all sort of noise like gravel in a plastic cup. As I looked at the surface, I could see several openings that allow air to pass through, and I imagine those holes act as funnels to scoop road debris and other stuff up from the road. So I set about removing the connectors. Not hard at all to find, and very simple to release.
I used the PET diagram as a guide before I went under the car, so knew where to look. In the following pics I've circled some of the fastening points. Nearly all are Torx - with the exception of two 11mm nuts along the rear edge of the panel that you can remove with a deep socket. The front panel has a leading-edge that is inserted into a recessed area to hold it in place, remember that when re-installing! It's hard to see in the pictures I took, but here is a shot that shows the panel installed -- I've also pointed-out one of the Torx screws that you will have to remove. And here is a shot of one of the Torx screws removed from the panel. They came out fairly easily. I used a ratcheting screwdriver and had each one out quickly. After you remove all of the screws, the panel doesn't just fall off. I had to work the front edge out a bit, and then pull the panel down from the rear over the two studs where the 11mm nuts held it in place.