Seibon 98-04 Lexus GS Series OEM Carbon Fiber Hood

Lightweight carbon fiber hood for the 1998 Lexus GS300, 1998 Lexus GS400, 2001 Lexus GS430

The Seibon HD9804LXGS-OE is a hand-laid 3K 2x2 twill weave carbon fiber over a fiberglass skeleton hood built specifically for the 1998 Lexus GS300, 1998 Lexus GS400. The UV-resistant gloss clear coat is factory-applied and ready to install. At up to 50% lighter than the OEM steel equivalent, it reduces unsprung weight for measurable gains in acceleration, braking balance, and cornering response.

Key Features

• Up to 50% Weight Reduction: Replaces the heavy OEM steel hood with carbon fiber construction, reducing unsprung weight for improved throttle response and front-end balance.
• 3K 2x2 Twill Weave Construction: High carbon-to-resin ratio delivers exceptional panel stiffness with a consistent, show-quality weave pattern across the entire surface.
• UV-Resistant Clear Coat: Factory-applied gloss finish resists yellowing and surface oxidation without requiring paint preparation.
• Direct Bolt-On Fitment: Pre-drilled mounting points align with OEM hinge hardware; uses factory latch and striker without modification.
• Seibon Fitment Guarantee: Test-fit verified for all US-model vehicles before production release.
• Heat Shield Recommended: Seibon recommends installing a heat shield on the underside to protect the clear coat from long-term engine heat exposure.

This Part Fits

Specifications

What's Included

• 1x Seibon carbon fiber hood
• Pre-drilled mounting holes for OEM hardware
• Hardware is not included; reuse OEM latch, striker, and hinge bolts

Installation

1. Gather tools: 10mm and 13mm sockets, torque wrench, flathead screwdriver, panel pop tool, painter's tape, and a second person to assist.
2. Tape fender edges with painter's tape before removal to prevent scratching.
3. Prop OEM hood fully open. Disconnect any headlight washer hoses, hood latch cables, and electrical connections routed through the hood.
4. Loosen (do not fully remove) the top two hinge nuts on each side, then fully remove the bottom two nuts.
5. With a helper supporting the opposite side, slide the OEM hood upward off the hinge slots and set it aside.
6. Transfer the latch, striker plate, and adjustment knobs from the OEM hood to the new carbon fiber hood.
7. Install a heat shield on the underside of the carbon fiber hood before mounting. Seibon strongly recommends this step.
8. Set the carbon hood onto the hinges. Thread all four hinge nuts by hand , two per side , before torquing anything.
9. Check gaps along both fender edges (target 3-5mm even clearance). Adjust hood position within the hinge slots as needed.
10. Torque hinge nuts in two passes: 10-15 Nm first, then 20-25 Nm final. Never exceed 30 Nm on carbon fiber panels.
11. Reinstall all hose clips, electrical connections, and headlight washer lines.
12. Close the hood 5-10 times to let it settle. Adjust bump stops as needed for flush fitment against fenders.
13. Hood pins are required for track use and strongly recommended for street use at highway speeds.

Frequently Asked Questions

The hood comes with a UV-resistant gloss clear coat applied directly over the carbon weave. No paint or primer is required. If you want to color-match it to your vehicle, a body shop can paint over the existing clear coat after light sanding and primer prep.

Seibon recommends hood pins for safety on all carbon fiber hoods. They are required for any track or competition use. For street use, the OEM latch holds the hood securely, but pins add an extra safety margin at highway speeds.

Yes. Seibon strongly recommends a heat shield on the underside of the carbon fiber hood. Engine bay heat can cause premature clear coat yellowing or cloudiness over time without one. Heat shield tape or a bolt-on heat deflector panel both work well.

No. Seibon strongly advises against reinstalling OEM gas struts or dampers. Carbon fiber hoods are significantly lighter than OEM steel, and the spring force of the struts can prevent the hood from closing properly or crack the carbon over time. Remove and store the dampers.

Seibon carbon fiber hoods weigh up to 50% less than the OEM steel hood for the same vehicle. The exact weight varies by model, but most hoods come in well under 20 lbs compared to 40-60 lbs for factory steel panels.

Seibon provides a fitment guarantee and a 6-month limited clear coat warranty. The fitment guarantee covers gaps wider than 1/2 inch at the fenders or fitment more than 1/4 inch higher or lower than the fenders. The clear coat warranty covers heavy cloudiness, bubbles larger than 3/8 inch, or shade shifts of more than one full shade within 6 months. Under the Magnuson-Moss Warranty Act, installing an aftermarket hood does not void your vehicle's factory powertrain or safety system warranty.

A mechanically experienced enthusiast can install this hood at home with basic hand tools. However, Seibon recommends having a professional with carbon fiber experience perform the final fitment and gap adjustment for best results. Always pre-fit before any cutting, painting, or drilling.

Seibon carbon fiber hoods are intended for off-highway and motorsport use. It is the buyer's responsibility to verify compliance with applicable state and local laws before street use.

WARNING: This product can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and reproductive harm. For more information go to www.P65Warnings.ca.gov.