C5 is the Mopar fender tag code for a "performance package" Barracuda where C2 would be for a formula s car. I have often found that people who even own these cars are not aware they exist. If you look at the photos you will see a 5 under the capital C on the fender tag. This would denote the designation of a performance package car. Commando 273, heavy duty suspension anti sway bar etc...My 4 gear Avatar car is a C5 car and my wife and I also have a C5 automatic car from California. There are some nice winding country roads where we live and these enhanced suspension packages make for a fun cruise especially with the 4 gear car.