What Does Each Tube Do in a Roll Cage?

A post gusset – Improves strength as the cage A pillar can be welded to the screen pillar (not applicable to all models).

Dash bar – Improves rigidity and side-impact strength.

Door X bars – Upgrades single door bar for significantly improved side impact protection; improves door aperture stiffness.

Front cross – Improves lateral stiffness of strut tops and bulkhead.

Hoop to A pillar tube – Designed to improve support for A pillars at roof level.

Hoop cross – X section now required by the latest regulations to improve roll over protection.

Lower rear stay – Triangulates loads from the rear struts so improving rigidity.

Mid rear stay – Adds further stiffness to rear section; improves side impact strength.

Rear strut brace – Improved bodyshell stiffness enhances handling by feeding suspension loads into the base of the roll cage; can be used or seat harness mounting in some models.

Rear X – Stronger than the simple single diagonal tube. Gives additional strength to rear damper mounts.

Roof cross or roof ‘V’ – Increases roll cage rigidity and safety in the event of a roll over; essential in later model rally cars.

Screen pillar support – Important for latest generation saloons with a steeply raked windscreen to provide additional support to the top of the A pillar/roof section. Now required by the latest FIA regulations.

Seat harness tubes – Needed for wrap-over seat belts. Safety improved with shorter belt length and better belt angle.

Single roof diagonal – Lighter than a full roof cross but provides less protection – acceptable for race cars.

Triangulation tubes to front struts – Allows the front suspension loads to be fed into the whole cage structure; provides protection for occupant’s feet. It also improves side impact protection and increases the load capacity of the ‘A’ pillars/lateral hoops.

Tunnel brace – Improves side impact protection and supports the main hoop in the event of a roll over.