Understanding WTAC: Classes


Yokohama World Time Attack Challenge competitors are split into four classes. Each class represents not just a level of modifications and overall development of the car but a segment in the time attack community and culture.

The heavily restricted Clubsprint is designed to accommodate owner-drivers on modest budgets. Considerably less restricted Open is the domain of performance workshops eager to show off their capabilities. Largely unrestricted Pro and Pro Am are the playground of big budget builds with extreme aero and engines often producing in excess of 1000hp.

Below is a quick guide to understanding the basic rules each class has to comply with.


Clubsprint Class is the “street” class with major restrictions on aero, body kits, suspension, tire size and many other aspects. This class’ focus is on clever vehicle set up and driver skill rather than radical modifications. It’s the best class to see closely-matched, like-minded people competing against each other in comparable vehicles.

Minor modifications are allowed to aero and body panels but strict restrictions are in place to minimise costs. Vehicles can lose no more than 5% from their original tare weight making carbon fibre components almost redundant. Engine modifications are free which results in some very high powered cars belting around on true road tyres, but the engine must remain from the same manufacturer and have the same number of cylinders (or rotors) as the stock car. Sequential gearboxes are not allowed, nor are any cars on the Supercar List (Ferraris, Porsches, R35 GTRs etc).

The vehicle must also have some form of registration ie rally rego or unregistered vehicle permit meaning lights etc must work. And most importantly, professional drivers are not permitted to drive in this class. So if you have a car you regularly take to the track and you want to tick WTAC off your bucket list, Clubsprint is where you want to start.


Cars: registered with minor modifications
Drivers: amateur drivers only
Tyres: Advan Neova ADO8 control tyre
Current Champion: Daniel Meredith, BYP Racing Honda Civic – 1:39.2740



Open Class is one of the most popular and often the largest class at World Time Attack Challenge. This is where you see serious privateers mixing it up with the big tuning houses. Behind the wheel, talented amateur drivers take on the pros in some seriously modified weaponry.

This class also has restrictions on aero but is far less restrictive than the Clubsprint class. Lexan windows (with the exception of windscreen) are allowed as are carbon fibre body panels. Sequential gearboxes are also permitted.

Cars range from high powered GTRs, Evos, RX7s, Hondas and WRXs to old school 240Zs with crazy engine conversions. Many notable Australian motorsport identities often feature on the drivers’ list as the event keeps attracting some very high profile racers. Weight reduction plays a big part in this class as these cars are permitted to reduce their tare weight by up to 15%.

Nitrous injection is permitted in this class, although only in naturally aspirated cars.

The permitted aero mods make this “mechanical grip” class exciting to watch with lap times at the pointy end getting close to what the V8 Supercars are doing around Sydney Motorsport Park.


Cars: tuner-based, high powered cars with moderate aero
Drivers: professionals or amateurs
Tyres: Yokohama Advan A050 semi slick control tyre
Current Champion: Nathan Morcom, Royal Purple / Spartan EVO – 1:29.2950



This is the first of the “aero” classes and it runs under the same rules as Pro Class with one big exception: no professional drivers.

Because of these restrictions this is a very popular class for “owner-drivers” who want to race at the top level against other like-minded enthusiasts on a level playing field without the pressure of competing against seasoned, professional drivers.

Nitrous injection is permitted in this class, although only in naturally aspirated cars.

This class is getting very close to Pro in terms of lap times so don’t let the “no pro drivers” rule fool you, these guys might be amateurs but they are very quick!


Cars: extreme aero, 1000+hp, extensive usage of carbon fibre panels and unlimited engine mods
Drivers: amateurs only
Tyres: Yokohama Advan A050 semi slick control tyre
Current Record: Mick Sigsworth, PMQ Evo – 1:25.75


This is the domain of the “big guns” and is the premiere class of World Time Attack Challenge. The winner of this class currently holds the outright tin top lap record at Sydney Motorsport Park.

The vehicles are largely of carbon fibre construction although they must retain the original floor pan making fully tubular construction or composite monocoque style vehicles ineligible. These cars often boast horsepower levels over 1000hp and, with the help of Nitrous injection as well as up to 20% reduction of their original weight have a frightening power to weight ratio.

The real key to their lap times though is in the aerodynamics. All of the fastest cars have professionally designed aero kits often by ex-Formula One or Indy Car engineers that allow for corner speeds that are virtually impossible in any other form of sedan racing. Most of the drivers in this class come from the highest levels of motorsport with many competing professionally in Japanese Super GT, Indy Car, V8 Supercar and American Le Mans.

Like any form of professional motorsport, competing at this level is not a cheap exercise with many of the fastest vehicles costing up to half a million dollars and requiring a team of engineers and mechanics to keep them running. This is the fastest, most prestigious class at the World Time Attack Challenge and one that has the eyes of the world every year.


Cars: extreme aero, 1000+hp, extensive usage of carbon fibre panels and unlimited engine mods
Drivers: professional or amateur
Tyres: Yokohama Advan A050 semi slick control tyre
Current Champion: Tim Slade, MCA Suspension Nissan Silvia – 1:22.1920


Understanding WTAC

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