Why was GTR banned from racing?

The technology was banned in 1993. Thanks to its turbocharged straight-six and genius all-wheel-drive system, the R32 Skyline GT-R was unbeatable in Australian touring car racing. ... Mechanical gremlins prevented the car from winning any races, but its downforce system was banned before it could reach its potential.May 10, 2016Nine Race Cars So Good They Were Banned - Road & Track