a.
Rear wings and rear diffuser must not protrude by more than 200mm above the highest point of the roof or from the rearmost point of the Standard bodywork / bumpers.
b. Front spoiler must not protrude more than 200mm from the foremost point of the Standard bodywork / bumpers. c.
Any Aerodynamic Device( including extended wheel arches) must not protrude more than 200mm from the vehicle, measured at the sides from a point on the waistline directly below the Standard door mirror, and from the Standard bodywork / bumpers.
d. No Aerodynamic devices can be located directly above the bonnet of the car. e. Flat floors are permitted. f.
g.
Any Aerodynamic Device must be rigidly secured to the entirely sprung part of the vehicle( rigidly secured means not having any degree of freedom) and must remain immobile in relation to the sprung part of the vehicle( active aero is not permitted).
Any Aerodynamic Device or construction that is designed to bridge the gap between the sprung part of the vehicle and the ground is prohibited under all circumstances.
17. Regulations for Open Wheel Single Seat Racing Cars 17.1. Dimensions
17.1.1.
Maximum width ahead of front wheels Maximum width behind front wheels Maximum height of any part wider than 1100mm ahead of the front wheels Maximum height
1500mm 1400mm Not to exceed the top of the front wheel rim
900mm from the ground Maximum rear overhang 1500mm behind rear wheel axis.
17.1.2. Maximum height is measured with the car in any condition and Driver aboard. Safety roll-over bars and air boxes are not included in this measurement.
17.2. Wheels
17.2.2. Twin rear wheels are permitted.
Motorsport UK National Competition Rules 2026 Edition 2
Chapter 14 Appendix 4- Technical Regulations 552