CACC Rule Change Proposal
RCP-2026-6288

20.8 Seat Mounting
20.8.1 It is required for GT category cars and recommended for IP category cars that the driver's seat
be firmly mounted to the structure of the car. This is also mandatory for IP car that have had the
original equipment driver’s seat replaced with another. In cars where the seat is upright (most
common in GT and IP/IT cars) the back of the seat shall be firmly attached to the main roll hoop,
or its cross bracing, so as to provide aft and lateral support. Bulkheads, firewalls, rear decks, or
similar structures of suitable strength may be used as a substitute for the main roll hoop or cross
bracing to provide the required seat back support.
20.8.2 Where a car is fitted with a seat complying with FIA standard 8855/2021 or 8855/1999 the seat
must be mounted according to the manufacturer’s instructions. If these instructions omit the
seatback mountings, the entrant should present a copy of those instructions at scrutineering.

20.8.1 It is required for GT category cars and IP category cars that the driver's seat be firmly mounted to the structure of the car. This is also mandatory for IP car that have had the original equipment driver’s seat replaced with a proper race seat. In cars where the seat is upright (most common in GT and IP/IT cars) the back of the seat shall be firmly attached to the main roll hoop, or its cross bracing, so as to provide aft and lateral support. A spreader bar(s) of minimum total area of 20 square inches, minimum thickness of 0.1875 inches (4.76 mm) and no dimension less than 2 inches, shall be fastened to the seat to spread impact load into the seat back. Bulkheads, firewalls, rear decks, or similar structures of suitable strength may be used as a substitute for the main roll hoop or cross bracing to provide the required seat back support.

20.8.2 Where a car is fitted with a seat complying with FIA standard 8855/2021 or 8855/1999 the seat must be mounted according to the manufacturer’s instructions. If these instructions omit the seatback mountings, the entrant should present a copy of those instructions at scrutineering. Where the seat is noncompliant with this rule or seat age exceeds the manufacturer’s recommendations, mounting in accordance with 20.8.1 may be accepted at the discretion of the Chief Scrutineer.

To clarify the seat mounting and bracing requirement and allow for acceptance of common sense deign.