SuperTT Technical Regulations

SuperTT – Technical Regulations.

  1. Philosophy

Super Tin Tops is intended to be a circuit racing Group for highly modified automobiles bridging the gap between modified production based, and space frame competition automobiles. It is aimed at Club level competitors who desire to exercise their engineering as well as driving skills.

Automobiles which may comply with these technical regulations but have a demonstrated performance well in excess of the remaining field may be excluded from competition in this Group at the discretion of the Event Organisers. Each such exclusion shall occur only after consultation with the relevant entrant and with due regard to appropriate notice being given.

Automobiles that do not comply with these regulations but in the opinion of the Event Organisers have performance and design broadly compatible may be invited to compete in this Group.

  1. Eligibility

To be eligible for Super Tin Tops, the automobile shall be developed from a road registrable closed automobile using a steel monocoque bodyshell. Automobiles utilising demountable chassis rails shall not be excluded by this definition. Open automobiles fitted with a hard top of either metal or a rigid composite material, shall be deemed to comply with this requirement. All-wheel drive vehicles are eligible, subject to certain engine and drivetrain restrictions, and may be converted to two wheel drive. GT cars are not eligible for Super Tin Tops.

No modifications may be made to the bodyshell save as permitted in these regulations.

Note to competitors: Body shells from V8 Supercars including Ford AU and Holden VT models onward do not comply with this requirement as they have numerous internal reinforcement panels deleted when compared to the relevant production body shell.

  1. Bodyshell
    • It is permitted to modify the bodyshell of the automobile as follows. Any opening created by the removal of metal must be closed in by the addition of welded in panels to maintain the integrity of the bodyshell.
    • It is permitted to modify the wheel wells to provide clearance for replacement wheel assemblies.
    • It is permitted to modify the floorpan to facilitate the fitment of replacement drivetrain assemblies.
    • It is permitted to add box sections to the rear floor area to allow for the fitment of additional or replacement suspension arms.
    • It is permitted to modify the floorpan to provide clearance for the exhaust and mufflers. Under no circumstances may the rocker panels be modified save for the removal or realignment of the pinch weld seams.
    • It is permitted to strengthen jacking points and/or fit air jack systems.
    • It is permitted to make holes for the passage of fuel, air or oil lines and electrical wiring.
    • The upper radiator support panel may be made removable to facilitate engine removal.
  2. Body Panels
    • Doors may be modified by the removal of metal, but must retain the window frame, door skin, standard hinges, external handle and door catch assembly. Doors must be able to be opened from the outside without the aid of tools The driver’s door must have an internal release mechanism. The driver’s door must have a flat panel fitted to the inside to prevent the driver’s arm from entering the door cavity. This panel may be original, or made of aluminium or carbon/Kevlar composite. Straight carbon fibre is not acceptable unless it is incorporated into a crushable structure of at least 10mm thickness.Where there is no moving glass in the driver’s door, it is recommended that the driver’s door cavity be filled with flame resistant polyurethane foam.
    • Where wheel arch flares are fitted, the rear edge of the rear doors may be modified by the removal of metal to provide clearance for replacement wheel assemblies. Any opening created must be closed by a welded panel.
    • Where wheel arch flares are fitted, mudguards and rear quarters may be modified by the removal of metal to provide clearance for replacement wheel assemblies. Any opening created must be closed by a welded panel.
    • The bonnet may be modified by the removal of reinforcement panels on the underside provided that it retains the original hinge placement, its external shape and can still be securely fastened. It is permitted to cut a hole in the bonnet to clear the engine provided that a bonnet scoop is fitted to cover protruding components. The bonnet scoop may have either a front or rear facing opening.
    • The bootlid may be modified by the removal of reinforcement panels on the underside provided that it retains its original hinge placement, external shape and can still be securely fastened.
  3. Windscreen and Glass

All moving and fixed glass, except for the windscreen, may be removed, or replaced with clear polycarbonate. Moving glass may be fixed in position. The windscreen must be retained and be of laminated glass.

  1. Body Kit

A body kit of plastic or composite material may be fitted. No part of the body kit may protrude more than 100mm from the original profile of the automobile when viewed from above. The kit may consist of:

  • Front and rear bumper bars, including airdams, undertrays and diffusers
  • Side skirts and door mouldings
  • Wheel arch flares
  • A rear spoiler, or rear wing which may not extend above the height of the top of the roof
  • A bonnet scoop
  • A roof mounted fresh air vent, of height not more than 50mm above the roof surface
  1. Suspensions, Wheels and Tyres
    • The front suspension is free provided that it retains the original configuration (e.g. Macpherson strut or double A-arm). Suspension Pivot points may be re-located and the front subframe may be modified or replaced.
    • There rear suspension may either be retained in its original configuration, or be replaced with a live or dead beam axle located longitudinally by a 4 link system. In either case suspension pivot points may be relocated, and all suspension components are free. The rear subframe is free.
    • Wheels are free in regard to diameter and method of mounting. Where a single nut is used to mount each wheel, a positive retention mechanism must be fitted to prevent the nut coming loose. The sum of the defined rim width of all four wheels shall not exceed 44”.
    • Tyres are free. Only air or nitrogen may be used to fill the tyres. The use of tyre warmers to pre-heat the tyres prior to a session is prohibited. Tyres must not be repaired or re-treaded. It is permitted to add grooves to tyres.
  2. Engine
    • Two wheel drive automobiles: The engine is free, but must not exceed 7 litres swept volume unless a larger engine is fitted as standard whereupon that engine may be retained. Forced induction may be utilised on engines under 4.5 litres swept volume. The location and orientation of the engine within the engine bay is free. Engine mounts are free but no part of the engine block/cylinder heads, or rotor housing/endplates, may extend rearwards of the original firewall.
    • All wheel drive automobiles: The original cylinder block and head(s) must be retained. The engine is otherwise free. Engine mounts are free. 
  1. Transmission/driveline
    • Two wheel drive automobiles: The clutch, flywheel and bell housing are free. The gearbox is free provided that it has no more than 6 forward gears and incorporates an operable reverse gear. Gearbox mountings are free. Driveshafts are free. The final drive is free as is the end of the car to which power is delivered. Two wheel drive automobiles must remain two wheel drive.
    • All wheel drive automobiles: The clutch and flywheel are free. The internal components of the gearbox and final drive are free but the casings must remain standard. Driveshafts are free.
  2. Other Systems
    • The fuel system is free. The complete fuel system must be isolated from the cockpit, save for fuel lines where the only joints may be at the front and rear bulkheads.
    • The electrical system is free. Each automobile must have functional tail and stop lamps. At least one functional electrically powered windscreen wiper must be fitted.
    • The brake system is free, but must be configured so that the brakes still work on two wheels should a leak occur in any part of the system.
    • Each lubrication system is free. Coolers, pumps and reservoirs must not be located in the cockpit.
  3. Interior
    All interior trim, except for the upper section of the crash pad, may be removed. The driver’s seat must be located entirely to one side of the automobile on the same side as the original car. The steering column is free save that the steering wheel may be no further than 150mm rear of the rearmost position of the standard wheel. The locations of the brake, clutch and accelerator pedals are free
  4. Safety
    • Each automobile competing must be fitted with a full 6 point safety cage.
    • Each competitor must use a safety harness with at least 4 straps in contact with the driver.