This is a closed club invitation series for saloon cars raced prior to 31st December 1966.

1)        The bodywork must be totally representative of the car as raced in that period
2)        Windscreen and side glass may be replaced with polycarbonate
3)        Headlights, brake lights and rear indicators must be in working order
1)        Cars must retain their original interior, except for carpets and passenger seats which may be removed
2)        The driver's seat may be replaced by a modern style racing seat
3)        Seat belts must be a minimum four point harness
1)        A roll cage is mandatory (for cars which lap Zwartkops in less than 90 seconds)
1)        The standard suspension must be retained and mounted on the original mounting points provided by the manufacturer. Suspension components may be modified and rubber bushings may be replaced with a alternate materials
2)        Spring rates are free, but the original type of spring must be retained, locate in the original mounting points and carry the full weight of the car
3)        Cars with leaf spring type rear suspension may fit a maximum of two anti-tramp rods and a Panhard rod to provide lateral location of the rear suspension
4)        Anti-roll bars are free
5)        Shock absorbers may be replaced, but must locate on the original mounting points on the body, chassis and suspension. Coil over units are not permitted, unless fitted as standard equipment by the manufacturer
1)        Brake master cylinders and pedal boxes are unrestricted
2)        Front and rear brakes may be upgraded, but calipers are restricted to four piston type units
3)        Brake pad and brake shoe material is free
1)        Wheel rim diameter may be increased to 1 inch over that which was provided as standard by the manufacturer. Wheels must be representative of the style used in that period
2)        Only the following treaded racing tyres are eligible for the series:
a)        Dunlop CR65/ Dunlop Direzza
b)        Hoosier Street TD
c)        Goodyear Blue Streak
1)        The noise emitted by the system may not exceed 105dB when subject to the test procedure set out by MSA
1)        Cars must use an engine that conforms to the same basic configurations as raced in that period
2)        Engine configuration:
a)        'V' or 'in-line' cylinders
b)        Number of cylinders
c)        Camshaft position - block or OHC
d)        Number of valves per cylinder
e)        Oil system - dry sump may only be fitted subject to written permission from the committee
f)        Ignition system - electronic ignition systems are permitted
g)        Carburetion - period type carburetors
3)        Engine capacity may only be increased as follows:
a)        Up to 1200cc by 50%
b)        From 1200cc to 1800cc by 25%
c)        Above 1800cc by 15%
1)        The gearbox or transaxle may be the original or a replacement unit derived from a standard production unit by the same manufacturer
2)         The gearbox or transaxle may not have more than 5 forward speeds
3)        The clutch and method of operation is unrestricted
4)        The type and location of the axle must be retained
5)        Gear ratios are free and any type of limited slip diff unit may be used
1)        The engine, gearbox and rear axle must remain in the original position
2)        The minimum weight of the car may not be less than 10% below the manufacturers stated excise mass for the model raced
3)        Car preparation must comply with the General Competition Rules and Regulations (GCR's) as specified in the annual MSA handbook
In the interest of costs, public interest and practicality of the formula, promoters will have maximum circuit time cut-offs. With modern technology and set-up development, it is very difficult to derive a compatible set of regulations. These cut-off times will be printed in the event regulations for the event, and will assist in curbing development work on the vehicle beyond what they were in the day. At Zwartkops, the top class cut-off for legends Saloons will be 76 seconds. A 1.4% variance will be tolerated under certain track conditions. However, this will only be allowed if at least two other competitors have achieved a similar time on the day. Once a car is deemed to be faster than the cut-off time, the committee will request the car to be detuned, or leave the series.