The anomaly that sees both 105 coupes and Alfetta GTV's as both sports and touring cars is the allowance for two door cars originally homologated as sports cars, which were based on a sedan, to be allowed to be homologated as touring cars as well. Other examples are the Torana, XA-XC Falcons, XJS etc. This homolgation ran out at the end of 1986 which was why the GTV6 was no longer allowed as a touring car.
Group S is the CAMS Category for Historic Production Sports Cars without competition history. ie. new cars can be built, they don't have to be cars that raced in the period. Eligible cars are from the period up to the end of 1977 (plus run on models - ie 105 coupes plus Alfetta GTV thru to 1981). Group N Touring cars only go to the end of 1972 hence no Alfetta or 75.
The beauty of Group S is that they are reletively cheap to build and race and there are plenty of events you can compete in from Club sprint days to Historic race meetings to 1hr production sport car races to Tarmac rallies.
Grids are large (54 cars at the 2007 Phillip Island Historic) and the racing is close. AROCA VIC is running a Group S competition based around the Club's Sprint Days and the major Victorian Historic meetings. There are quite a few cars now complete and about another dozen in the pipeline.
For more info on Group S including rules and specifications go to:
http://www.alfaclubvic.org.au/compon...68/board,19.0/