2016-2020 Honda Civic Si Rear Diffuser V1 (Coupe)
- 2016-2020 HONDA CIVIC SI COUPE REAR DIFFUSER V1
- - Fitment: 2016-2020 Honda Civic Si Coupe
- - 3 pc Construction
- - Made from Aerospace Lightweight ALUMINUM no ABS PLASTIC!!!!
- - Made in the USA
- - Comes fully CNC'd and professionally powder coated
- - Comes pre-drilled
- - Fitment Guaranteed
- - Hardware is included
- - Professional install highly recommended
A rear diffuser is an automotive aerodynamic modification typically found mounted on the vehicle’s underbody located at the rear of the vehicle, underneath the rear bumper. As a vehicle is in motion, air flowing in the underbody is typically at high-speed and has low-pressure. The design and purpose of a diffuser are to help reduce drag and to create downforce by facilitating the airflow underneath the vehicle’s underbody. A diffuser is used to increase the air volume along its full length, thus creating a void that must be filled by air. This in turn creates a Venturi effect, meaning the air flow is accelerated at the beginning of the diffuser creating a low pressure, thus creating downforce. As the air travels along the full length of the diffuser, the high velocity air is eased back into normal velocity matching the ambient velocity at the rear of the vehicle reducing overall drag. With the addition of vertical “fins” attached to the diffuser, this helps to optimize the diffusers efficiency by ensuring that all air being drawn into the diffuser is from the underbody and isn’t being drawn from the upper body surfaces. A diffuser is best optimized with the addition of a front splitter to help mediate the underbody’s airflow.
Customer Reviews
The diffusers are very well build. Kind of confusing at first to put on but I figured it out.
All of AeroFlow’s parts are of high quality! So, if you’re looking for fantastic aero, this is that place!
That said, these kits come with zero install instructions. They say to have a professional install the parts, but even pros may have a hard time figuring out how to properly orient the pieces. Luckily, some folks online have posted detailed instructions, so, ensure you find those.
Otherwise, it’s a great mix-match kit set up!