Based off the Hispano-Suiza HS21 concept made in 2002 by Marzel, the SR21 is a dedicated race car. It’s manufactured by Sun-Red racing who have been actively campaigning them since 2007 in the International Open GT Championship.
The car is powered by Judd’s V12 engine displacing 244 cu. in. (4000cc) which produces 500 bhp. It uses a steel tube frame with a carbon fiber body.
Although the SR21 was designed under GT2 regulations it is only permitted in the International Open GT championship where is has achieved mediocre performance. The SR21 doesn’t meet the FIAGT’s road-car production requirements.