GTA Class Rules
The Spirit of the GTA Class
To provide a competitive class which allows people to modify and improve race cars without too many restrictions while still retaining a period appearance.
General specifications
Cars must conform to current MSNZ Handbook Schedule A, and the specifications below. For class identification each car must have a GTA class series banner decal.
Safety
A safety structure that complies with the requirements of Schedule A for the type of vehicle concerned must be fitted and, for all closed vehicles, a safety cage must be fitted. A replacement seat without backrest adjustment or a competition seat and 4, 5 or 6 point harness complying with Schedule A must be fitted for use by the driver. Novice drivers must display 3 stripes 25mm wide by 300mm long on the top R/H corner of the rear window; after participating in 4 series race meetings the stripes may be removed.
Exterior
Overall appearance must be suitable for the car’s period. Alfa Romeo race car replicas and common period production body kits, (e.g. Zender/Trofeo/GTAM) are permitted. Minor wheel arch flares, and front spoilers are permitted provided they are visibly suitable for the period. The bodyshell must remain complete and may not be cut except as required for the foregoing. Nonstandard rear spoilers are permitted only if part of a fitted period bodykit or required to create a replica. Bumpers may be removed when not forming part of the body shape. Undertrays are permitted provided that they are required to create a replica or are otherwise discreet and not externally visible. Headlights can be substituted with covers or mesh. Doors, bonnet, boot, nose cones, rear panels and mudguard skins can be made of composite materials, but they must be the same shape as the original. Interior framework of doors/bonnet/boot can be lightened. The vehicle shall be smartly maintained and presented in a finished state.
Glazing
All glazing other than windscreen may be substituted with alternative transparent material. The driver’s side window must have an opening to allow for external hand signals. It is strongly recommended that rear screens be 5mm thick.
Interior
If fitted, a front passenger seat must meet the requirements of Schedule A. Dashboard, door trims and side panels similar to original must be fitted.
Chassis
The body must remain original with only the following exceptions. Minor alterations for stiffening, lightening of non-structural areas and to facilitate safety items, are permitted. Boot floor may be replaced with suitable rigid material and can also be modified to accommodate fuel cell. Front inner guards may be modified to accommodate engine auxiliaries (e.g. cooler, carbs, water pump etc.). Transmission tunnel may be modified to allow for replacement gearbox or diff only. All of the above must follow sound engineering practices. Battery may be relocated.
Engine
Must be Alfa Romeo and can be changed between models. Configuration and number of cylinders are to remain as originally fitted for any production variant of that model. Turbocharging and supercharging are permitted only if original and factory fitted for the particular engine and vehicle combination. All other modifications are otherwise free.
Exhaust
Free
Transmission and differential
Gearbox and clutch are free. Differential must retain original location and type (Live/independent), otherwise free.
Suspension
All components must be of the original design and material type for the model and perform its original function using original mounting points. Reproduction of factory/works modifications is permitted. Additional chassis mounting points may be used. Otherwise free.
Brakes & Wheels
Free.
Tyres
Tyres must be appropriate for the wheel size and comply with the standard for a Road Tyre or Treaded Tyre as defined in Schedule A. Aspect ratio is limited to 50% minimum, unless a greater width was fitted by the manufacturer for the model concerned. Aspect ratio is limited to a minimum of 50%, unless the manufacturer specified a lower aspect ratio for the model concerned.