The front splitter is a World Challenge homologated part saving development costs; you can see the little silver rectangular World Challenge sticker in the middle of the splitter showing it is an approved part. The openings in the frontend are covered with removable mesh inserts to keep debris such as chunks of race tire marbles out.
A StopTech Trophy brake kit which anyone can buy is used for racing. Heck, I think Kojima has them on half of his street cars. The fact the StopTech Trophy kit is used for racing speaks to their legit performance status. The coil-overs are not terribly exotic and the brake ducting is just your standard neoprene tubing. The parts used are all very high quality but still easily within the reach of your average upper middle class guy.
Another simple and low-cost racecar modification is the addition of a mesh screen to the opening in the front fender liner. In looking at the front wheel area, all of the body panels are factory pieces. There is also an absence of fancy carbon fiber bits and ducts; pretty much everything is left stock keeping costs down.
No crazy diffusers or wide body fenders here. Just a World Challenge homologated wing mounted to the rear hatch.
As the Cayman is a mid-engine car, it also has a rear trunk. The trunk has been gutted of course for race duty.
Here is a simple modification; the factory rear hatch latch mechanism was replaced with a simple wire and loop saving weight and a potential failure mode of the stock latch mechanism failing. Another simple modification is the bumper stop thingy in the corner of the hatch opening to better support the rear hatch.