Tuner Shocks and Struts - Full Rules

1. Shocks and Strut Replacement Allowances:

A. Any shock absorbers may be used.

B. Shock absorber mounting brackets which serve no other purpose may be altered, added, or replaced, provided that the attachment points on the body/frame/subframe/chassis/suspension member are not altered. This installation may incorporate an alternate upper spring perch/seat and/or mounting block (bearing mount). The system of attachment may be changed.

C. The number of shock absorbers shall be the same as standard.

D. No shock absorber may be capable of adjustment while the car is in motion, unless fitted as original equipment.

E. MacPherson strut equipped cars may substitute struts and/or may use any insert. This does not allow unauthorized changes in suspension geometry or changes in attachment points (e.g., affecting the position of the lower ball joint or spindle). It is intended to allow the strut length changes needed to accommodate permitted modifications which affect ride height and suspension travel.

2. The following additional allowances apply to cars originally equipped with separate spring and shock absorber assemblies.

A. Coil springs may be relocated so they encircle the body of the shock absorber in a “coilover” configuration.

B. Coil spring perches may be modified, added, or replaced and their position may be adjustable.

C. Additional bolt holes may be drilled for coilover assembly mounting brackets. This does not permit any modifications to the frame or unibody beyond the allowed mounting holes.