MRT Fiesta ST Forza 5 Edition. In game and was playable on XBOX ONE at SEMA 2013
http://www.youtube.com/watch?v=oLzpkm6nWSg&feature=c4-overview&list=UUPs03nDv5iPkOiAOE9ofltA
Fiesta ST Rally Sport Exhaust by MRT. This turbocharged go kart sounds bad to the bone IMO!
http://www.youtube.com/watch?v=0pbvDSBYAMY&feature=c4-overview&list=UUPs03nDv5iPkOiAOE9ofltA