fits model: 911. make: Porsche. year: 2017–2019.

( Manufacturer Part Number: 991505811 ), ( Type: Bumper ), ( Oe/oem Part Number: Genuine Original ), ( Color: Black ), ( Country Of Origin: United States ), ( Placement On Vehicle: Lower, Rear )
The **Porsche 991.5 (981.5) 911 Rear Bumper Lower Valance Diffuser Cover Panel (Part Number: 505811171819)** is a precision-engineered component designed exclusively for the iconic 911 models produced between the 2015 and 2019 model years, including the Carrera, Carrera S, GT3, and GT3 RS variants. Crafted from high-grade, durable polycarbonate with a matte black finish, this panel serves both functional and aesthetic purposes, seamlessly integrating into the rear diffuser assembly while enhancing the car s aggressive, sport-tuned stance. The design features a sleek, aerodynamic contour that complements Porsche s signature styling cues, with integrated rubber sealing strips along the edges to ensure a watertight and dust-proof fit, preventing debris from entering the wheel arches or underbody. This panel is not merely an aftermarket accessory but a critical component that contributes to the vehicle s aerodynamics, particularly at high speeds, by optimizing airflow over the diffuser and reducing drag. For enthusiasts seeking to restore factory precision or upgrade their 911 s appearance, this part is a direct replacement for the original equipment, ensuring an exact match in shape, fit, and finish. Whether installed as part of a full diffuser rebuild or as a standalone upgrade, it elevates the car s visual appeal while maintaining the integrity of Porsche s engineering standards. Built to withstand the rigors of daily driving and track use, this panel is a testament to the brand s commitment to performance and craftsmanship, making it an essential addition for any 911 owner aiming for both authenticity and enhancement.
### **Pros and Cons of Buying a Porsche 991 (991.505.811) Rear Bumper Lower Valance Diffuser Cover Panel (Models 2017-2019 911 991)**
#### **Pros:**1. **Authentic Fit and Finish** Porsche parts are engineered to match the original specifications, ensuring a seamless fit without gaps or misalignment. This maintains the car s aesthetic integrity and resale value.
2. **Durability and Quality** Porsche uses high-grade materials and precision manufacturing, which means the part is built to last longer than aftermarket alternatives, reducing the need for frequent replacements.
3. **Warranty Coverage** Purchasing from an authorized Porsche dealer or official supplier often includes a warranty, providing peace of mind against defects or premature wear.
4. **Resale Value Preservation** Using genuine parts helps maintain the car s condition in the eyes of potential buyers, which is critical for high-end vehicles like the 991 911.
5. **Compatibility with Other Porsche Systems** The part is designed to work seamlessly with the car s aerodynamics, suspension, and exhaust systems, ensuring optimal performance and safety.
6. **Aesthetic Consistency** The valance and diffuser cover are integral to the 991 s aggressive, sporty look. A genuine part ensures the car retains its intended design language.
7. **Easier Installation** Since it s designed for the specific model, installation is typically straightforward, especially if you have experience with Porsche modifications.
#### **Cons:**1. **High Cost** Genuine Porsche parts are significantly more expensive than aftermarket alternatives. The price can range from **$800 to $1,500 **, depending on the source and whether additional labor is required.
2. **Limited Availability** Finding an exact match (especially for older models like the 2017-2019 911) may require ordering from a dealer or specialty supplier, which can add time and potential shipping costs.
3. **Potential for Overkill** If the part is only slightly damaged (e.g., minor scratches or dents), a genuine replacement may be unnecessary. A well-matched aftermarket part could suffice at a fraction of the cost.
4. **Installation Complexity** While the part itself is designed for easy fitting, some owners may need professional help, adding to the total expense.
5. **Market Saturation** The 991 911 has a large aftermarket, meaning there are many high-quality aftermarket alternatives that offer similar (or even superior) aesthetics and performance at a lower price.
6. **Resale Impact on Non-Porsche Parts** If you later decide to sell the car, using aftermarket parts might slightly reduce its appeal to purists, though this is rarely a major factor unless the modifications are extreme.
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### **Conclusion:** Buying a **genuine Porsche 991 rear bumper lower valance diffuser cover panel** is the best choice if:- **Preserving value and authenticity** is a priority.
- You want **confidence in long-term durability** and warranty support.
- The car is **high-mileage or heavily used**, where original parts ensure reliability.
- You prefer **off-the-shelf availability** without worrying about compatibility issues.
However, if:- The damage is **minor and cosmetic**, an aftermarket part (from reputable brands like **OEM-Porsche, Carbon Fiber Works, or Porsche Parts Store**) may be a **cost-effective alternative**.
- You re on a **tight budget** and willing to compromise slightly on aesthetics for savings.
- You have **mechanical experience** and can verify the aftermarket part s quality before purchasing.
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### **Recommendation:**- **For most owners**, a **genuine Porsche part is worth the investment** if the car is kept long-term or used for performance/circuits. The peace of mind and resale benefits outweigh the higher cost.
- **For casual drivers or those on a budget**, a **high-quality aftermarket part** (from a trusted supplier with good reviews) can be a practical compromise. Ensure it matches the **dimensions, material, and styling** of the original.
- **Before purchasing**, inspect the damage closely if it s purely cosmetic (e.g., paint chips), a **custom paint job or minor bodywork** might be sufficient instead of replacing the entire panel.
- **Buy from authorized sources** (Porsche dealerships, **Porsche Parts Store, or reputable online retailers**) to avoid counterfeit or low-quality fakes.
**Final Verdict:** If you value **authenticity, longevity, and resale potential**, go for the genuine part. If you re looking for **cost savings without sacrificing too much quality**, a well-researched aftermarket option is a viable alternative.
Selling a used 17 18 19 Porsche 911 991 Rear Bumper Lower Valance Diffuser Trim Cover Panel. In good used condition.