Installing bonnet vents is a popular modification for both performance and styling. Whether you're upgrading a track car, restoring a classic, or simply enhancing engine bay ventilation, this guide will walk you through the process step by step.

​⁠🔍⁠​ Why Install Bonnet Vents?

• Improved Cooling: Helps hot air escape the engine bay, reducing under-bonnet temperatures.
• Enhanced Aesthetics: Adds a motorsport-inspired or aggressive look.
• Performance Boost: Supports airflow management for track and high-output engines.

​⁠🔧⁠​ Tools & Materials Needed

​⁠🧰⁠​ Tools:

• Jigsaw or angle grinder
• Drill with step bits
• Metal file
• Measuring tape & masking tape
• Safety glasses & gloves
• Rivet gun or bonding kit (if required)
• Clamps (optional for alignment)

​⁠📦⁠​ Materials:

• Bonnet vent kit (universal or custom)
• Cutting template (usually included)
• Rust-proof primer (for metal bonnets)
• Sealant or adhesive (if bonding vents)
• Optional: mesh backing for insect/debris protection

​⁠📐⁠​ Step-by-Step Installation

1. Choose the Vent Placement

• Identify the hottest zones of the bonnet (typically rear-center or above the exhaust manifold).
• Ensure vents won’t interfere with bonnet support structure or bonnet latch.
• Mark the placement using masking tape.

2. Apply the Cutting Template

• Stick the template onto the bonnet in the chosen area.
• Double-check alignment and symmetry.

3. Cut the Bonnet

• Drill pilot holes in the corners of the template area.
• Use a jigsaw or angle grinder to cut along the template lines.
• Smooth edges using a metal file.
• Apply rust-proof primer to exposed metal edges.

4. Install the Vents

• Rivet-on or bolt-on: Align the vent, drill fixing holes, and rivet or screw it into place.
• Bond-on: Apply high-temp automotive adhesive or sealant, clamp in place, and allow to cure.

5. Finish the Installation

• Optional: Install mesh behind the vents for protection.
• Paint or touch up as needed to match bonnet finish.
• Refit the bonnet and test open/close clearance.

​⁠✅⁠​ Tips for Best Results

• Use automotive-grade primer and paint to prevent rust.
• Consider heat shields or insulation inside the bonnet near hot zones.
• Avoid placing vents where water ingress may affect sensitive components (e.g., ECU).
• For aluminium or fibreglass bonnets, ensure appropriate bonding materials.

​⁠📍⁠​ Where to Buy Bonnet Vents (UK)

• Car Builder Solutions – Universal vent kits & accessories
• Forge Motorsport – Performance vent kits
• Pro Alloy Motorsport – Custom pressed louvre panels
• eBay UK – Budget and OEM-style vents

​⁠🧪⁠​ Legal Note (UK DVSA)

Bonnet modifications should:

• Not compromise pedestrian safety
• Not interfere with structural integrity
• Pass MOT (Ensure no sharp edges or loose fittings)