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- Porsche 918 Spyder 4.6L

Fits:
Porsche 918 Spyder
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Diagram ref no 1
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91856511
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Hardtop & Targa Tops - Structural Styling & Weather Protection
Hardtops and Targa tops provide essential structural rigidity, weather protection, and exterior styling for Porsche Cabriolet and Targa models. Designed to replace or upgrade factory roof systems, these components improve cabin refinement, enhance vehicle stiffness, and deliver a cleaner, coupe-inspired profile.
At Design911, our Hardtop & Targa Tops category features precision-engineered solutions for Porsche owners seeking improved durability, performance feel, and long-term reliability—without compromising fit or aesthetics.
What Do Hardtops & Targa Tops Do?
Hardtops and Targa tops enhance both structural performance and everyday usability.
Core Functions:
- Provide weatherproof protection from rain, wind, and noise
- Increase chassis rigidity and driving stability
- Improve thermal and acoustic insulation
- Enhance exterior styling with a coupe-style roofline
- Protect the interior from UV exposure and environmental damage
These components are ideal for year-round driving and performance-focused builds.
Why Do Hardtops & Targa Tops Fail?
Factory and ageing roof systems can degrade over time due to mechanical and environmental stress.
Common Failure Causes:
- Seal deterioration leading to water leaks
- Warping or cracking from UV and heat exposure
- Worn latching or mounting mechanisms
- Noise issues caused by ageing materials
- Reduced rigidity compared to fixed or upgraded roof systems
Older or frequently removed tops are especially prone to wear and misalignment.
Why Upgrade Your Hardtop or Targa Top?
Upgrading delivers tangible benefits in comfort, durability, and driving confidence.
Upgrade Advantages:
- Improved sealing and weather resistance
- Enhanced structural rigidity and reduced flex
- Lighter, stronger materials for improved performance feel
- Refreshed styling for older Porsche models
- Long-term reliability and reduced cabin noise
Hardtops and Targa tops from Design911 are designed for precise fitment and long-term usability.
Highlights
- Porsche-specific hardtop and Targa top solutions
- Designed for durability, refinement, and styling
- Improved insulation and structural performance
- Suitable for daily driving and enthusiast builds
- OEM-fit or performance-upgrade options