

From the supergt site

Suspension

Suspension type on the original vehicle may be freely modified and altered.

However, if the suspension mounting points on the chassis/monocoque are modified, the suspension must still work normally when the engine has been dismounted.

All suspension arms must be made of metallic materials.

Spring and shock-absorber are free of restriction.

Adjustment of anti-rollbars can be made mechanically only by the driver, and only when the car is in motion.

Anti-rollbar adjustment by any other means is not permitted when the car is in motion.

Brake systems

There are no restrictions on brake materials or mechanisms as long as they comply with the other regulations listed separately.

Fenders:

On each side of the car, fender dimensions may be extended

(increased in width) up to 5cm over the width of the original vehicle,

Engine modifications:

Modifications to cylinder capacity are permitted.

Supercharging devices are also allowed.

Reinforcement of cylinder head and cylinder block is permitted.

Crankshaft and connecting rods modifications are unrestricted.

Material restrictions

Composite materials

(Including carbon and kevlar):

Permitted in the relevant parts or areas if authorized in the regulations, or used as standard on the original car and original engine.

Titanium and ceramics:

Apart from connecting rods, intake and exhaust valves, valve retainers, heat shields, brake caliper pistons and superchargers, titanium and ceramic materials can be used on specific areas of the car, but only if these materials are used as standard on the original vehicle and engine.

I won't go on!