RM Engineering GT4 MK2/Ring Spec/235iR/240iR Wing Mount Trunk Reinforcement Sleeve Kit

Reinforce the rear wing mounting points of your BMW trunk lid with the RM Engineering Wing Mount Trunk Reinforcement Sleeve Kit.

Developed for RM Engineering GT4 MK2, Ring Spec, M235iR, and M240iR rear wing systems, this reinforcement kit provides additional structural support around the trunk mounting locations. It is specifically designed for motorsport-style wing installations that use the BMW GTS-style mounting configuration.

Large rear wings can transfer substantial aerodynamic and mechanical loads into the trunk panel during high-speed driving, track use, and repeated loading cycles. Without proper reinforcement, these concentrated forces may place excessive stress on the outer and inner trunk skins, potentially causing movement, deformation, cracking, or damage around the mounting holes.

The reinforcement sleeves create a rigid connection between the upper and lower trunk structures, helping distribute wing loads through a stronger and more stable mounting point. This provides improved support for the wing uprights while reducing localized stress on the trunk panel.

Each kit includes four precision-machined M6 reinforcement sleeves designed to be installed directly into the trunk lid at the rear wing mounting locations.

Compatible RM Engineering Wing Systems

Designed for use with:

• RM Engineering GT4 MK2 Rear Wing
• RM Engineering Ring Spec Rear Wing
• RM Engineering M235iR Rear Wing
• RM Engineering M240iR Rear Wing
• Other compatible BMW GTS-style wing mounting configurations
• Compatibility may vary depending on the wing mount, trunk lid, and installation configuration. Confirm mounting dimensions before installation.

Key Features

• Reinforces the trunk mounting points for rear wing installations
• Designed for RM Engineering motorsport-style rear wings
• Compatible with BMW GTS-style mounting configurations
• Creates a rigid connection between the upper and lower trunk structures
• Helps distribute aerodynamic loads across reinforced mounting points
• Reduces localized stress around the trunk mounting holes
• Helps prevent movement, cracking, and deformation of the trunk panel
• Provides increased structural support for high-downforce rear wings
• Includes four precision-machined M6 reinforcement sleeves
• Suitable for metal, composite, and carbon fiber trunk lids
• Recommended for track, time-attack, and high-performance applications

Construction & Design

Each reinforcement sleeve is precision-machined to provide a secure mounting surface between the rear wing hardware and the internal trunk structure.

The locating section of the sleeve is designed to fit closely within the prepared trunk opening. Once properly installed, the reinforcement sleeve supports the wing mounting hardware and transfers load through both layers of the trunk lid rather than concentrating force on the outer trunk skin alone.

Correct hole sizing and sleeve alignment are essential. The sleeve should sit securely and evenly inside the trunk structure without excessive movement or clearance.

Installation Requirements

Professional installation is strongly recommended. Accurate measuring, drilling, alignment, and permanent bonding are required.

For metal trunk lids, welding the reinforcement sleeves to the trunk structure is recommended for maximum rigidity and long-term structural support.

For composite or carbon fiber trunk lids, the sleeves must be secured using a high-strength structural body panel adhesive suitable for bonding metal to composite materials.

Test fitting is required before welding or applying adhesive. The diameter of each mounting hole must closely match the locating section of the reinforcement sleeve to ensure a secure and properly supported installation.

Minor adjustments may be required due to differences in trunk construction, manufacturing tolerances, wing mounts, and installation configurations.

Important Installation Notes

• Metal trunk lids require welding for maximum structural support
• Composite or carbon fiber trunk lids require high-strength structural adhesive
• Do not rely solely on the outer trunk skin to support the rear wing
• Precisely measure and confirm all mounting locations before drilling
• Confirm that every sleeve sits securely against the internal trunk structure
• Welding or structurally bonding the sleeves significantly increases mounting rigidity
• Incorrect installation may damage the trunk lid or compromise the rear wing mounting system