Explain Ponyboy’s words when he visits Johnny in the hospital: “I figured that southern gentlemen had nothing on Johnny Cade”

Ponyboy is referring to the gallant, Southern gentlemen, he and Johnny had read about in Gone With the Wind, and comparing them to Johnny. In Ponyboy's mind, Johnny was the epitome of bravery, sefl-sacrifice, and heroism..... more than the heroes in the novel could ever be.