GT3 Center Radiator and Functional Smile Vent on 987 Cayman

Many people install the “smile vent” from the GT3 onto Caymans and Boxsters for the look, but it is possible to use OEM parts to make the vent fully functional on both the 987.1 and 987.2. The two main benefits to this are that you no longer are dumping hot, turbulent air under the front of the car (bad for aerodynamics), and you get a substantially larger center radiator.

This installation is not a purely bolt-on affair, though, and there are some factors to consider.

1. The parts are not cheap. I spent well over $1,000 (2024) in parts alone.
2. You must use the 997 GT3 radiator, which is larger and hangs lower than the 987’s center radiator. I would recommend doing this only if you run a flat bottom splitter to help protect the radiator protruding from the factory bumper cover.
3. The center radiator bracket and ducting interfere with the factory 987.2 (and presumably .1) side radiator inlet ducting.
4. This installation takes a lot of time, patience, and trimming to get everything to fit and function well. If ducting (and looks) is less of a concern to you then this may be a smaller factor.

This article is not intended to be a step-by-step guide, but should help point you in the right direction if you opt to attempt this yourself. Please double check part numbers via Porsche parts catalogs and diagrams, and plan your installation and modifications carefully. This is just the way I made this setup work for me, perhaps you can improve upon it (and I’d love to hear about it if so).

Shout out to Kyle Hoyer in the Track Caymans Facebook group for the original parts list and idea.

Part Numbers

• Main duct – 997-504-487-92
• Upper duct – 997-504-489-81
• Coolant hoses (987.1)
  • 997-106-638-92
  • 997-106-639-92
• Coolant hoses (987.2)
  • 997-106-638-91
  • 997-106-639-91
• Rubber mounts (x4) – 930-113-430-00
• Radiator Plug – 996-106-545-71
• Mounting nut (x2) – PAF-003-923
• Duct to bumper – 997-575-141-90
• Retaining frame – 997-504-485-81
• Smile vent – 997-575-327-93-01C
• Radiator
  • OEM: 996-106-037-75
  • CSF: CSF7053

After photos:

987.2 Center Radiator vs 997 GT3 Center Radiator

How far the 997 GT3 radiator hangs down below the factory bumper

I was worried this wouldn’t work with the factory 987.2 AC lines in place, but it does! I had to very slightly tweak the hard lines to ensure nothing rubbed. You can also see I zip tied the upper duct , it was a little warped without being held in place.

Lower duct and bracket

If you use a CSF radiator, the lower mount must be trimmed to fit because it’s larger than the OEM radiator. I believe this is not needed if you use OEM. Be careful when cutting, this part is made of carbon fiber.

You can see here just how tight this setup is inside the factory bumper, and why substantial trimming is needed.

I (sloppily) trimmed back some of the center radiator mount to help make room for the side radiator ducts. Be careful not to remove too much material and weaken the mount too much.

The exact cuts I made to the side ducts are not pictured, but I substantially trimmed down the side ducts to fit inside the bumper and maintain their functionality. This required many small cuts, test fitments, and more cuts.

Some more final photos of the end result