Targa/Cabrio vs Carrera wheel wells? C4S vents (less lift, no extra drag) possible?

The C4S and 40AE (and probably the Turbo) vent air from the radiator into the front wheel well, directed outwards. This, combined with the C4S front bumper and various parts in between provide a significant reduction in front end lift with no drag penalty, all without the very low, fragile, and very, very expensive to install and repair GT3 bumper. I'd really like to have less front lift, and I really don't want extra drag. So I'm now working on this for my Targa. But I've run into a bit of a puzzle, and I'm hoping someone has some insight into the differences between Carrera and Targa/Cabrio wheel well linings. These linings have three parts: front, middle, and rear. All three are different on the C4S. I think all three will fit a Carrera, because I think all three are used on the 40AE (strangely, the PET is silent on this). Or with luck, the key, front piece from the C4S can be attached to the normal mid piece, and you don't need the other C4S pieces. (Anyone know?) However, the Targa and Cabrio use a different front piece from the Carrera. So even if the front C4S piece fits the Carrera, it might not fit the Targa or Cabrio. I'm wondering why on earth the Targa and Cabrio need a different wheel well. They do have stiffer springs, dampers, and anti-roll bars, but I wouldn't think any of this would require a different front wheel well piece. Perhaps a different suspension arm or geometry? By the way, the front piece is number 1 in the PET diagram, part number 996 504 123 00 for the C4S. On page 243 (as Adobe counts the pages). I'll try to post a picture from the PET later. Similarly, the C4S conversion requires a different air duct (number 8 in the PET diagram), and again, the Targa and Cabrio versions of these parts are different from the Carrera parts. So while I'm pretty sure these fit on the Carrera, I'm not sure about the Targa and Cabrio. Does anyone know why these two pieces are different on the Targa and Cabrio? Or whether it's possible to install the C4S equivalents on a Targa or Cabrio? (Or of any slight modifications that might be needed to make it possible? It it's just something like needing clearance for a thicker suspension arm, that might be easy.) I'll try to share what I learn and update on progress. In the meantime, any insight into this would be greatly appreciated!!

C4S uses Turbo radiators and brackets. Yes they are different from C2/C4 parts. So C4S also uses Turbo wheel well liners which bolt up to the rad brackets differently and are 2-piece. There are writeups here and elsewhere on how to mod the C2/C4 wheel well liners to vent into the wheel wells. That's the cheapest way.

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Thanks for the quick response! I'm beginning to fear however that my question may somehow not have been clear. My question is about Targas and Cabrios. I have seen the write ups elsewhere. Indeed, one of the most detailed such discussions is probably a thread I started years ago. And I think I now understand how to do what I now want to do (which is a full C4S bumper/duct/radiator/bracket/wheel well conversion) on a Carrera. But I'm not there yet re. how to do it on a Targa or Cabrio. Because while I'm 99% sure the two C4S wheel well parts I mentioned are compatible with a Carrera, I'm not sure they are compatible with Targas and Cabrios. Because for some reason, Targas and Cabrios don't use the Carrera parts, so what is compatible with a Carrera might not be compatible with a Targa/Cabrio. Any insight would be greatly appreciated re. whether these three C4S parts are compatible with a Targa or Cabrio, or can easily be made compatible, or about why they might not be compatible (which may help me figure out a solution). Thanks!!!

I did a bunch of research on this a few months ago and did not run across any reference to C2 parts being different for cab/targa. Do you have part numbers showing it?

As far as I know all front ends are compatible across all 996.2's as long as it is the full set of parts. The front tub is different for the awd vs. rwd cars and that may be a concern? @zbomb put a Turbo bumper on his c2 and needed a filler piece underneath where the center radiator exhaust is on the C4S/Turbo.

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I did sort of promise to post images from the PET, didn't I? OK, time to upload some images. Here is the diagram, followed by the table with part numbers, etc.. As can be seen in the table, there are three versions of the parts labeled 1 and 8 in the diagram: A regular version, a C4S version, and a Tagra/Cabrio version. (I didn't post the next page, where of course the right side number 8 part also comes in three such versions.) Hope this clears things up a bit.