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.

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.