Unlike some of the CF piece that's a copy of some existing design of OEM/GRP/FRP piece, the development cost is almost next to none. When a piece like this that's developed from the ground up. These are the stages that we've gone through:
This is the back end of the spoiler to ensure maximum surface to mount onto the trunk and it's form fitting to the most complex contour piece of a Z4 roadster. The fitment is spot on and most the pictures posted are without the spoiler mounted. It just rested on top of the trunk since I haven't decided if I want to paint match the top part of the spoiler or not.
The closed off design is for the ease of installation, longevity on the carbon finish and to keep the moisture out. I didn't like some CF pieces that's hollow on the back side. It's hard to install and fitment will be off from car to car. I thoroughly enjoyed this project and had a lot of fun!
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