Roll Cage Installation for Track Cars: Everything You Need to Know
Upgrading your track car with a roll cage is one of the most impactful safety and performance improvements you can make—but it’s not as simple as bolting in a few bars. At GSM Performance, we help customers every week understand the differences between cage types, materials, and installation requirements. In this guide, we’ll walk you through everything you need to know: from bolt-in vs. weld-in choices to legal considerations, safety tips, and why the right preparation is essential.
Whether you’re installing a full FIA-homologated cage for competitive motorsport or a bolt-in option for track days, following the right process—and choosing the right equipment—can make all the difference.
Bolt-In vs. Weld-In Roll Cages
Bolt-in cages are popular for track-day cars that still see road use. These systems use pre-formed steel tubes that bolt to mounting plates, which are welded into the vehicle’s floor or chassis. This setup allows for future removal of the cage or reinstallation of trim for road use. Some bolt-in kits, like those from Safety Devices, include removable elements like rear diagonals and door bars, giving more flexibility for dual-purpose vehicles.
Weld-in cages, on the other hand, are ideal for dedicated race cars. They require the bars to be welded directly to the car’s chassis or floor, offering greater rigidity and reduced flex under load. While they provide superior safety and stiffness, they also demand a fully stripped interior and more extensive installation work by experienced professionals.
Cage Materials: What Are They Made From?
Roll cages are made from specific grades of high-strength steel to meet FIA or Motorsport UK regulations. Common materials include:
- T45 Steel – The most popular choice in the UK for high-performance builds due to its strength and ease of bending and welding.
- 25CrMo4 / 4130 Chromoly – Slightly stronger than T45 but trickier to weld.
- CDS (Cold Drawn Seamless) – Used in most bolt-in cages like those from Safety Devices; heavier but easier to work with.
Each material has unique properties for weldability, strength, and compliance. Aluminium, notably, is not permitted under FIA or Motorsport UK rules.
Installation Process: Stripped vs. Unstripped Interiors
Stripped Installations
In competition builds, the interior is completely stripped to reveal bare metal. This allows for clean, precise welding of the mounting plates and bars. The process typically involves:
- Removing seats, carpets, panels, and airbags.
- Cleaning and prepping the floor and pillars.
- Test fitting the hoop and crossbars for helmet clearance.
- Welding mounting plates and final bar installation.
This approach ensures maximum safety and adherence to homologation standards but is labor-intensive.
Unstripped Installations
For road cars, unstripped interiors are more common. These builds retain more of the car’s trim and upholstery. In this case:
- Only essential components like seats and sections of carpet are removed.
- Holes may be trimmed into interior panels for cage tube clearance.
- Lower-profile hoops may be used to fit under the headliner.
While more visually appealing for dual-purpose cars, unstripped installations require more precise measurements and trimming.
Safety, Legalities & Best Practices
Installing a roll cage isn’t just about performance—legal and insurance implications must be taken seriously:
- Padding: Any bar within 150 mm of the driver’s head must be padded with FIA-homologated foam.
- Airbags: Side and curtain airbags often need to be removed or disabled when installing cages.
- DVLA Compliance: Modifying structural elements may reclassify your car under DVLA rules. Be cautious of substantial changes that affect classification (e.g., converting to a “Q-plate”).
- Insurance: Always notify your insurer post-installation, as this significantly changes your vehicle’s risk profile.
Proper welding techniques (TIG/MIG on clean steel), protecting wiring, seam sealing joints, and testing seat/harness fit post-installation are all vital to a professional-grade install.
Manufacturer Options and Kits
Safety Devices
With over 50 years of experience, Safety Devices provides both bolt-in and weld-in FIA/MSUK-compliant kits using E355+N CDS tubing. Their bolt-in kits are modular and easy to install with road-going flexibility.
Custom Cages
Known for their high-spec T45 and 25CrMo4 weld-in kits, Custom Cages is ideal for serious race builds. Many of their kits require fully stripping the car and fabricating under-floor mounting plates.
JP Cages
Great for track-day drivers, JP Cages makes easy-to-install kits with pre-welded plates and DIY-fit bars using E355+N steel. They offer “stripped” and “unstripped” variants depending on your vehicle interior.
Common Challenges & Tips for a Smooth Installation
- Clearances: Always test bar positions and ensure helmet and seat clearances are within FIA specs.
- Welding Access: Tight spaces like footwells or under roofs are hard to weld. Use magnets, extra hands, and creative positioning.
- Trim Protection: Shield upholstery with fireproof blankets during welding.
- Paint and Finishing: After welding, apply primer and paint to protect the steel.
- Final Safety Check: Double-check bolts, welds, and ensure everything is properly torqued and aligned. Verify driver seating position and harness routing.
Final Thoughts – Build Safe, Build Smart
Roll cages are a critical upgrade for any serious track car—but they demand proper planning and execution. Whether you’re installing a modular bolt-in Safety Devices system or a full weld-in Custom Cages kit, always follow best practices for welding, measuring, and fitment.
If you’re unsure where to begin, visit us at GSM Performance. We supply cages and kits from the UK’s top manufacturers and can advise you on the best option for your car and racing goals. Plus, we can help you find the right seat, harness, and accessories to complete your interior build safely and legally.