ANATOMY OF A SPORTS SEDANS
The wild, winged Sports Sedans are Motor racing’s most modified machines. Under broad rules the category promotes freedom of expression as a legitimate means to an end – and that end is on track performance, lot’s of it.
Thundering V8’s, whistling turbo’s and wailing rotary engines abound in Sports Sedan racing, and these are installed in seemingly infinite car combinations……..all remarkably evenly matched.
A leading Sports Sedan is a purpose built racing chassis covered by a mostly fibreglass replica of a recognised 2 or 4 door sedan. A massive power to weight ratio is achieved when highly modified engines, up to 6-litres in capacity, motivate these lightweight sedans. Whilst today’s V8 Supercars produce about .44 horsepower per kilogram the leading national Sports Sedans average about .59 horsepower per kilogram.
At some tracks the Sports Sedan lap record is 2 seconds lower than the V8 Supercar lap record.
A full field of National Championship Sports Sedans is indeed an exciting spectacle from the very moment they arrive on the track. The flared fenders, huge wheels and tyres, low front spoilers and large rear wings make these cars stand out as exciting purpose built racing sedans. Presently the leading cars boast around 650 horsepower, over 500 ft pounds of torque and weigh in at around 1000 – 1100 kilograms.
To be eligible cars competing must derive from vehicles recognised by CAMS as touring cars. Also some vehicles which have at times been seen as borderline sports/touring, such as the Mazda RX7, are eligible.
Technology has been embraced by most National competitors with computerised fuel injection and engine management systems the most common choice. More recently we have seen computerised design in suspension geometry and set-up to assist teams in achieving the ultimate performance package.
Just as there is a wide variety of chassis design and body preference, there is variety once again in the transmission. The most popular choice is the Hewland transaxel. This type of transmission is widely used in Le-Mans Sportscars, Indycars and Formula One. Other forms of transmission from V8 Supercars, American Trans-am and NASCARS are also widely used. Recently competitors using these transmissions and sophisticated live rear axle setups have been challenging for the lead and this auger’s well for more unpredictable close racing at the front of the pack.
Sports Sedan races are held in every State and Territory in Australia. Local club and State Championship races give enthusiasts the opportunity to race in self built or modified cars, whilst the Australian Sports Sedan Championship brings together the pinnacle of Australian Sports Sedan competitors and equipment to determine our National Champion.