This part is irrelevant to promoting their product, and concerns the factory spoiler.
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Overview: The optional factory Tesla rear spoiler provides sleek looks with optimized airflow characteristics to enhance efficiency as well as high speed stability.
Result: As expected, this product is not just for looks, it indeed performs improvements in high-speed stability and drag reduction. The vehicle’s total drag was reduced by 2.3% and the rear downforce was increased over baseline by 34.7%. This reduced the total drag coefficient (Cd) by 0.005.
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