Carbon Fiber Rear Diffuser Upgrade for Nissan R33 Skyline GT-R

Enhancing the Rear End of Your Skyline R33 GTR with a Carbon Fiber Diffuser

The Nissan Skyline GT-R (R33) is an iconic Japanese sports car that first debuted in 1995. Nicknamed "Godzilla" for its brute power and performance, the R33 GT-R quickly became a tuner favorite thanks to its robust RB26DETT twin-turbo 2.6L inline 6-cylinder engine. Even today, the R33 GT-R remains a sought-after platform for both drag racing and circuit driving. One popular modification for the R33 GT-R is adding a rear diffuser to help manage airflow under the car for increased downforce and stability.

What is a Rear Diffuser?

A rear diffuser is an aerodynamic device installed under the rear bumper of a vehicle. It helps smooth out airflow underneath the car to decrease drag and increase downforce. The diffuser does this by accelerating airflow and reducing air pressure under the vehicle. This helps "suck" the car downward and improve high-speed stability.

Diffusers work by forcing air to expand and slow down inside the diffuser chamber. This expansion creates a low pressure area under the car, generating downforce. Diffusers also help smooth out the turbulence created when air flows underneath the vehicle. Overall, a good diffuser can provide significant aero benefits without adding a lot of visual bulk.

Benefits of Adding a Diffuser to an R33 GT-R

There are several key benefits of adding an aftermarket diffuser to a Nissan R33 Skyline GT-R:

• Increased downforce - More downforce over the rear axle improves grip and stability when cornering at high speeds.
• Reduced drag - Smoothing airflow underneath the car cuts down on drag and turbulence for better acceleration.
• Improved handling - Extra downforce over the rear wheels allows later braking and higher cornering speeds.
• Enhanced traction - Pushing the rear end down helps maximize traction when launching and exiting corners.
• Cooler running temps - Improved underbody airflow aids in engine and drivetrain cooling.
• Custom looks - An aftermarket diffuser stands out and gives the rear end a more aggressive appearance.

For hardcore R33 GT-R enthusiasts, adding a diffuser is one of the best ways to optimize the car's handling and performance at high speeds. The extra downforce and drag reduction provides grip and stability exactly where it's needed most - over the rear axle.

Carbon Fiber vs. FRP Diffusers

When choosing a rear diffuser for the R33 GT-R, two popular options are carbon fiber or FRP (Fiberglass Reinforced Plastic). Here's an overview of each material:

• Carbon Fiber - Made from woven carbon fiber cloth set into resin. Very lightweight, rigid, and durable. More expensive but provides superior strength-to-weight ratio. Thermally stable and resistant to temperature fluctuations.
• FRP - Composite material made by reinforcing plastic with layers of glass fiber. More flexible and affordable than carbon fiber. Not quite as strong or lightweight but still very durable. Can withstand minor impacts without damage.

Carbon fiber diffusers are lighter, stiffer, and more premium-looking. They also hold up better in extreme use cases like hardcore track days. However, FRP diffusers offer a more budget-friendly option with nearly similar durability and performance. Ultimately carbon fiber works best for all-out race cars, while FRP suits daily drivers and weekend track toys just fine.

Installing a Diffuser on an R33 GT-R

Here is an overview of installing an aftermarket rear diffuser on an R33 Nissan Skyline GT-R:

1. Lift the rear of the car and support it securely on jack stands.
2. Remove the rear bumper cover and unbolt the stock diffuser or undertray.
3. Temporarily test fit the new diffuser and check fitment. Some minor trimming or adjustment may be needed.
4. Clean all bonding surfaces thoroughly and scuff for better adhesion.
5. Apply adhesive promoter/activator to the bonding areas.
6. Apply two-part epoxy adhesive to diffuser and car body.
7. Carefully align and press the diffuser into place, clamping as needed while adhesive cures.
8. Allow adhesive to fully cure for several hours or overnight before driving.
9. Reinstall rear bumper cover and any other removed components.
10. Lower vehicle and enjoy the improved aesthetics and performance!

The factory undertray or OEM diffuser will need to be removed to install the new aftermarket diffuser. This may require cutting, grinding, or drilling out spot welds. Take care not to damage the bumper, bodywork, or any electrical wiring during removal. Most diffusers secure to the rear underside with heavy duty adhesive and some additional mechanical fasteners.

Maintaining Your Carbon Fiber or FRP Diffuser

Like any aerodynamic addon, an aftermarket diffuser will need periodic cleaning and inspection to keep it looking and performing its best:

• Rinse regularly with water to remove dirt, debris, salt, and grime buildup
• Clean gently with soap and water or an appropriate auto detailing spray
• Avoid using harsh chemicals or abrasives that could dull or damage the finish
• Inspect adhesive joints and reseal as needed to prevent separation or leaks
• Check for cracks, impact damage, or fluid leaks that could compromise performance
• Remove any stuck-on debris like mud or gravel which could block airflow

Proper maintenance will help an aftermarket diffuser last for years and maintain its good looks. Catching any damage early can also prevent costly repairs down the road. For carbon fiber diffusers, applying a sealant/protectant can further enhance durability and longevity.

Conclusion

Adding a carbon fiber or FRP rear diffuser is a great way to improve the aerodynamics of an R33 Nissan Skyline GT-R. The diffuser produces crucial downforce over the rear axle for better grip and high speed stability. Along with style and appearance upgrades, it’s a smart performance modification for any R33 wanting to handle better on both street and track. With some care and maintenance, a diffuser can provide big aero benefits and unique styling for years to come.

FAQs

What are the main benefits of adding a rear diffuser to an R33 GT-R?

The main benefits are increased rear downforce for better grip and stability, reduced drag for better acceleration, and improved handling and traction at high speeds. A diffuser also enhances the visual appearance of the rear end.

What materials are commonly used for R33 GT-R diffusers?

The most popular materials are carbon fiber for its light weight and strength, or FRP (fiberglass reinforced plastic) which provides a more affordable but still durable option.

Is installing a diffuser difficult for a DIY mechanic?

Installing a diffuser requires removing the rear bumper and undertray, proper cleaning and prep, use of adhesives/fasteners, and careful alignment. It can be challenging but is doable for a knowledgeable DIYer.

How often should I clean and inspect my aftermarket diffuser?

It's recommended to rinse your diffuser regularly, do thorough cleanings as needed, and inspect adhesive joints and for any cracks or damage every few months. This helps maintain peak appearance and performance.

Will a diffuser void the factory warranty on my R33 GT-R?

Adding an aftermarket diffuser could potentially void warranties depending on your local laws and the policies of the manufacturer. Check before modifying to be sure.